JP2008129355A - Cleaning brush and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning brush capable of not only effectively removing toner from a photoreceptor, but also properly applying lubricant to the photoreceptor. <P>SOLUTION: The cleaning brush 12 has a brush fabric 22 that scrapes a solid lubricant 13, applies it onto a photoreceptor drum 1, and also removes toner adhering to the photoreceptor drum 1. The brush fabric 22 has a first brushing area 20a and a second brushing area 21a, which are mutually different in the characteristics. Each of the brushing areas 20a and 21a are disposed helically along each other, on the outer circumferential face of a shaft 23. In this way, combining the two kinds of brushing areas 20a and 21a of different characteristics makes it possible not only to appropriately remove the toner from the photoreceptor but also to properly apply the lubricant to the photoreceptor, in a compatible manner. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cleaning brush that applies a lubricant to a photoconductor provided in an electrophotographic image forming apparatus and removes toner from the photoconductor.

  In an electrophotographic image forming apparatus, an electrostatic latent image formed on a photoreceptor is visualized with toner. Most of the toner image obtained by the visualization is transferred to the recording paper in the transfer process, but a part remains on the surface of the photoreceptor after the transfer process. A cleaning blade is used to remove the toner in the remaining toner image.

  The cleaning blade scrapes off the toner particles adhering to the surface of the photosensitive member by performing a stick-slip operation by bringing the edge portion into contact with the surface of the photosensitive member. At this time, if the frictional force between the surface of the photoreceptor and the blade is large, the stick-slip operation by the blade cannot be performed smoothly, and the toner removal efficiency is lowered. In addition, the toner removal efficiency is also lowered when toner particles adhere to the surface of the photoreceptor.

  Therefore, many image forming apparatuses have a mechanism for applying a lubricant to the surface of the photoreceptor. By applying a lubricant to the surface of the photoconductor, the frictional force between the surface of the photoconductor and the blade is reduced, and the toner is less likely to adhere to the surface of the photoconductor. It becomes.

  Usually, the lubricant is applied by a brush roller. FIG. 12 is a top view showing a conventional technique and showing a shape of a brush fabric used for manufacturing a brush roller. FIG. 13 is a side view showing a configuration of a brush roller according to the prior art. FIG. 14 is an enlarged side view of the brush fabric shown in FIG.

  The conventional brush roller 100 is manufactured by winding a strip-like (rectangular) brush cloth 101 shown in FIG. 12 spirally around the outer peripheral surface of a cylindrical base body 102 as shown in FIG. The As shown in FIG. 14, the brush fabric 101 has a structure in which a brushing region 101a composed of a plurality of hairs in contact with the photosensitive member and the solid lubricant is supported by a base 101b. As the brush fabric, for example, a nylon material having a hair thickness of 30d, a hair density of 50 kf, and a hair length of 5 mm is used.

  In the brush roller 100, when the base body 102 is driven to rotate about an axis, the brushing region 101a slides against the solid lubricant and scrapes off the lubricant. The brushing area 101a applies the shaved lubricant to the photoconductor. In addition to the function of applying the lubricant, the brush roller 100 also has a function of scraping and removing toner particles adhering to the photoreceptor.

For example, Patent Documents 1 and 2 disclose image forming apparatuses including such brush rollers. In the cleaning device disclosed in Patent Document 1, the brushed region of the brush roller is made shorter than the length of the rotating shaft body of the roller, thereby providing spacers in the non-haired regions formed at both ends of the rotating shaft body. A device has been devised to suppress the slip of the roller. Further, in the cleaning device of Patent Document 2, a device is devised in which the lubricant particle size is reduced by applying the lubricant from the lubricant accommodating portion to the photoreceptor via two lubricant application brushes.
Japanese Patent Laying-Open No. 2005-165022 (released on June 23, 2005) Japanese Patent Laying-Open No. 2005-275166 (released on October 6, 2005)

  However, the conventional brush roller 100 has a problem that the ability to remove the toner from the photosensitive member is deteriorated because the toner is not discharged as soon as it is taken into the brushing region 101a. Furthermore, if toner accumulates on the hair in the brushing area 101a, the hair gradually becomes hard, which may damage the photoconductor. In particular, when the process speed of the image forming apparatus is increased, the area where the brushing area 101a abuts during one rotation of the photoconductor increases, so that the amount of toner taken into the brushing area 101a also increases. It becomes even more serious.

  Note that if the density of the hair in the brushing area 101a is lowered, the length of the hair is shortened, or the thickness of the hair is increased, the toner discharging property from the brushing area 101a is improved, but the photoconductor. Another problem arises in that the lubricant applied to the surface is uneven, or the amount of lubricant applied becomes excessive because the force for scraping off the lubricant is too strong. If the amount of lubricant applied becomes excessive, running costs are increased and the size of the solid lubricant needs to be increased, which requires extra space.

  The present invention has been made in view of the above problems, and provides a cleaning brush capable of achieving both effective toner removal from a photoreceptor and application of an appropriate lubricant to the photoreceptor. is there.

  In order to solve the above problems, a cleaning brush according to the present invention is a cleaning brush provided with a brush member that contacts and slides on a photoconductor and collects toner adhering to the photoconductor from the photoconductor. The brush member has a plurality of brushing regions that slide in contact with the photoconductor, and the plurality of brushing regions include hair density, hair thickness, hair material, and hair length. At least one of the above is different from each other.

  The ability to discharge toner from the brush member and the ability to apply a lubricant to the photoreceptor depend on characteristics such as the density of the hair, the thickness of the hair, the material of the hair, and the length of the hair in the brushing region. Here, it is difficult to achieve both discharge ability and application ability by a single brushing area. However, according to the above configuration, the brush member has a plurality of brushing areas having different characteristics, and thus is excellent in toner discharge. By combining the brushing area and the brushing area suitable for scraping or applying the lubricant, it is possible to achieve both toner discharge ability and lubricant application ability. Therefore, it is possible to achieve both effective removal of toner from the photoreceptor and application of an appropriate lubricant to the photoreceptor.

  In addition to the compatibility between the toner discharge capability and the lubricant application capability, various capabilities such as both toner discharge capability and charge removal capability can be achieved.

  In order to solve the above problems, the cleaning brush according to the present invention slides in contact with the photoreceptor and the solid lubricant, scrapes off the solid lubricant, applies it to the photoreceptor, and adheres to the photoreceptor. A cleaning brush provided with a brush member for collecting toner from the photoconductor, wherein the brush member has a plurality of brushing regions that slide in contact with the photoconductor and the solid lubricant, The brushing area is characterized in that the properties of the toner collected from the photoconductor to the outside of the brushing area and the scraping ability and / or application of the solid lubricant are different from each other.

  The ability to discharge the toner from the brush member and the ability to apply the lubricant to the photoreceptor depend on the characteristics of the brushing region. As described above, it is difficult to achieve both discharge ability and application ability with a single brushing area. However, according to the above configuration, the brush member has a plurality of brushing areas. By combining the region and the brushing region suitable for scraping or applying the lubricant, it is possible to achieve both the toner discharging ability and the lubricant applying ability. Therefore, it is possible to achieve both effective removal of toner from the photoreceptor and application of an appropriate lubricant to the photoreceptor.

  The plurality of brushing regions may have different hair densities, may have different hair thicknesses, may have different hair materials, or may have different hair lengths. May be different from each other. Of course, a plurality of these may be different from each other.

  As described above, the toner discharging ability and the scraping ability and application ability of the lubricant depend on the hair thickness, the hair length, the hair density and the hair material in the brushing region. By combining a plurality of brushing regions, it is possible to achieve both effective toner removal and appropriate lubricant application.

  The cleaning brush further includes a rotatable cylindrical base, the brush member is provided on the outer peripheral surface of the base, and each brushing region is formed in a spiral around the outer peripheral surface of the base. In addition, it is preferable that one brushing region is formed in a spiral shape along the other brushing region.

  According to the above configuration, the areas of the photoconductor and the solid lubricant that are in contact with the brush roller are sequentially rubbed by the brushing areas, and thus are in contact with any of the brushing areas. Accordingly, uneven application of the lubricant occurs in a part of the photoreceptor, toner is not sufficiently removed in the part of the photoreceptor, or the lubricant is excessively scraped off in the part of the solid lubricant. Therefore, the toner can be effectively removed from the entire area of the photoconductor, and the lubricant can be appropriately applied to the entire area of the photoconductor.

  The brush member is preferably composed of a plurality of brush fabrics, and each brush fabric preferably has the brushing regions having different characteristics.

  According to the said structure, the brush roller mentioned above can be easily manufactured by combining several different brush fabric.

  In addition, the plurality of brushing regions may include a first brushing region and a second brushing region having different characteristics from each other.

  As shown in the examples to be described later, it is possible to achieve both effective toner removal and appropriate lubricant application by using two brushing regions.

  The area ratio between the first brushing region and the second brushing region is preferably in the range of 30:70 to 70:30.

  If one brushing region is overwhelmingly larger than the other, the effect obtained by the other brushing region will be insufficient, but by setting the area ratio of the two brushing regions as described above, A brush roller that makes full use of the advantages of the brushing region can be realized.

  The first brushing region and the second brushing region may be different from each other in at least two of hair density, hair thickness, hair material, and hair length.

  As shown in the examples described later, the above configuration can achieve both effective toner removal and appropriate lubricant application.

  An image forming apparatus according to the present invention includes the above-described cleaning brush, the photoconductor, and the solid lubricant.

  According to the above configuration, since the cleaning brush described above is provided, the toner can be effectively removed from the photoconductor and the lubricant can be appropriately applied to the photoconductor, thereby forming an image with good image quality over a long period of time. can do.

  As described above, the cleaning brush according to the present invention is a brush member having a plurality of brushing regions in which at least one of hair density, hair thickness, hair material, hair length is different from each other, or the above The brush member has a plurality of brushing regions having different characteristics regarding the discharge of the toner collected from the photoreceptor to the outside of the brushing region and the removal and / or application of the solid lubricant. Therefore, as described above, it is possible to achieve both effective removal of toner from the photoreceptor and application of an appropriate lubricant to the photoreceptor.

Embodiment
An embodiment of the present invention will be described below with reference to FIGS.

  First, a configuration of a main part of an image forming apparatus equipped with a cleaning unit having a cleaning brush according to the present embodiment will be described. FIG. 2 is a longitudinal sectional view of the image forming apparatus 10 as viewed from the front side.

  As shown in FIG. 2, the image forming apparatus 10 forms a toner image (here, a monochrome image) according to image data on a paper P. The image forming apparatus 10 includes a photosensitive drum 1, and a charging unit 2, an exposure unit 3, a developing unit 4, a transfer unit 5, a fixing unit 6, and a cleaning unit that are configured to perform the Carlson process around the photosensitive drum 1. A unit 7 is provided.

  The photosensitive drum 1 is rotatably supported by a housing (not shown). The surface of the photosensitive drum 1 is charged to a predetermined uniform potential by the charging unit 2, and an electrostatic latent image corresponding to image data is written by the exposure unit 3. Thereafter, the electrostatic latent image is visualized using the toner by the developing unit 4 to form a toner image. The formed toner image is transferred by a transfer unit 5 onto a paper P fed from a paper feed tray (not shown) and sent to the fixing unit 6 together with the paper, where it is melted and pressed and fixed on the paper P. Is done. The paper on which the toner image is fixed is then discharged onto a paper discharge tray.

  On the other hand, after the toner image is transferred to the sheet P, the photosensitive drum 1 is subjected to the removal of the toner remaining on the surface by a cleaning unit 7 to be described later, and then the charge remaining on the surface is removed by a charge removal unit (not shown). At the same time, the charging unit 2 is charged again.

  As the charging unit 2, any of a contact charging method and a non-contact belt method such as a scorotron charger may be selected. Further, as shown in FIG. 2, the transfer unit 5 temporarily transfers the toner image visualized on the surface of the photosensitive drum 1 to a belt-like intermediate transfer member, and then transfers it to a recording sheet. A method may be used, or a toner image on the photosensitive drum 1 may be directly transferred onto a sheet.

  Note that the image forming apparatus 10 can form images on both the front and back sides of a sheet by switchback conveying the sheet. The image forming apparatus 10 is configured to form only a monochrome image, but may be configured to form a color image.

  Next, the cleaning unit 7 will be described in detail. FIG. 3 is an enlarged cross-sectional view showing the configuration of the cleaning unit 7. As shown in FIG. 3, the cleaning unit 7 includes a blade 11, a brush roller (cleaning brush) 12, a solid lubricant 13, a lubricant holding member 17, a toner recovery screw 15, and a flicker 16. The member is covered by the case 18.

  The blade 11 is for collecting toner remaining on the surface of the photosensitive drum 1, and is formed of a long rubber member whose longitudinal direction is the axial direction of the photosensitive drum 1. The blade 11 is arranged such that one long side is attached to the downstream side in the rotation direction of the photosensitive drum 1 through the opening of the case 18 and the other long side edge (corner) is in contact with the surface of the photosensitive drum 1. ing.

  The blade 11 dams the transfer residual toner remaining on the surface of the photosensitive drum 1 after the transfer of the toner image at a contact portion with the photosensitive drum 1, and scrapes and removes it while performing a stick-slip operation. The stick-slip operation is an operation in which the contact portion of the blade 11 with the photosensitive drum 1 moves in the rotational direction of the photosensitive drum 1 according to the movement of the surface of the photosensitive drum 1 and the elasticity of the blade 11 itself. This is a movement that repeats the operation of returning to the original position by force, and the movement of the edge of the blade 11 sliding on the surface of the photosensitive drum 1.

  The solid lubricant 13 is applied to the surface of the photosensitive drum 1 by the brush roller 12 and has a rectangular parallelepiped shape having the same width as the width of the photosensitive drum 1 in the longitudinal direction. The solid lubricant 13 is held by a lubricant holding member 17 and can be replaced when worn out and the remaining amount is reduced.

  The lubricant holding member 17 is designed to be slightly larger than the solid lubricant, and the rectangular solid solid lubricant 13 is bonded and fixed to the lubricant holding member 17 with a double-sided tape (not shown), or the solid lubricant 13 is lubricated. The agent holding member 17 can be fitted and fixed. Further, the lubricant holding member 17 may contact the brush with the solid lubricant 13 by its own weight instead of fixedly installing the solid lubricant 13. Further, both ends of the lubricant holding member 17 are supported by the case 18 so as to be movable in the brush direction so that the amount of shaving is not reduced as the solid lubricant 13 is consumed. It may be configured to move in the brush direction.

  The brush roller 12 is a cylindrical brush having substantially the same width as that of the photosensitive drum 1, and the shaft of the photosensitive drum 1 and the shaft of the brush are in contact with each other so that the tips of the brushes touch the surface of the photosensitive drum 1. They are arranged in parallel. The brush roller 12 is driven to rotate in the same direction as the rotation direction of the photosensitive drum 1, so that both slide in opposite directions at the contact portion.

  The contact portion of the photosensitive drum 1 with the brush roller 12 is downstream of the transfer portion in the rotation direction of the photosensitive drum 1, and the surface of the photosensitive drum 1 after the toner image is transferred and the brush roller 12. Are in contact with each other. The brush roller 12 scrapes off the solid lubricant 13 disposed on the upstream side in the rotation direction of the brush with respect to the contact portion with the photosensitive drum 1 and applies the scraped lubricant to the surface of the photosensitive drum 1. .

  As described above, the brush roller 12 applies the fine particles of the solid lubricant 13 to the surface of the photosensitive drum 1, thereby reducing the frictional force between the blade 11 and the surface of the photosensitive drum 1 and at the same time. Since the adhesion force of the toner to the surface of the drum 1 is weakened, the removal by the blade 11 is efficiently performed.

  For example, a fatty acid metal salt known as a metal soap can be used for the solid lubricant 13. As the fatty acid, for example, at least one fatty acid selected from the group consisting of stearic acid, palmitic acid, myristic acid, and oleic acid can be used, and as the metal, for example, zinc, aluminum, calcium, At least one metal selected from the group consisting of magnesium, iron, and lithium can be used. As a specific example, solid lubricant 13 is obtained by solidifying calcium stearate, zinc stearate, titanium stearate, calcium stearate, aluminum stearate, barium stearate, or magnesium stearate manufactured by Kanto Chemical Co., Ltd. Can be used.

  When the solid lubricant 13 absorbs water, the charging ability of the photosensitive drum 1 is affected. Therefore, it is preferable to use a solid lubricant 13 having a hygroscopicity of 0.5% or less. Further, porous powder such as porous glass or zeolite may be mixed into the solid lubricant 13 in order to remove discharge products.

  Further, the brush roller 12 has a function of scattering the toner adhering to the surface of the photosensitive drum 1 by being in contact with the photosensitive drum 1. Thereby, the removal by the blade 11 is performed efficiently. Further, the brush roller 12 is disposed at a position where the toner scraped and scraped by the blade 11 can be collected, and the toner scraped off by the blade 11 is removed by the scraping force of the brush tip. In addition to mechanical removal from the surface, it also has a function of collecting in the case 18.

  Flicker 16 is in contact with brush roller 12. In the present embodiment, the flicker 16 is a rectangular plate-like member having substantially the same width as the brush roller 12, and its longitudinal direction is parallel to the axis of the brush roller 12, and one long The sides (edges) are arranged so as to be in uniform contact with the brush roller 12. The flicker 16 has a function of dropping the toner adhering to the hair of the brush roller 12 into the case 18.

  A mechanism for discharging toner from the brush roller 12 by the flicker 16 will be described. First, when the brush roller 12 rotates, the tip of the hair of the brush roller 12 is caught by the flicker 16, and the hair is curved in a bow shape. When the brush roller 12 further rotates in this state, the tip of the hair is released from the flicker 16, and the hair tries to quickly return to the original shape (linear shape) by the elastic force. Thereafter, the bristles of the brush roller 12 quickly stop when the original shape (linear shape) is reached, but the toner adhering to the bristles tends to continue to move according to the law of inertia, so it falls off the bristles. It will do.

  Note that the brush roller 12 also performs the same interaction as described above with the photosensitive drum 1. That is, the photosensitive drum 1 plays the same role as the flicker 16 in dropping the toner attached to the hair of the brush roller 12. Therefore, although the flicker 16 is not an essential member, it is preferable to provide the flicker 16 because the dischargeability of the toner from the brush roller 12 is enhanced. Further, the flicker 16 is preferably arranged so as to be in contact with the base of the hair of the brush roller 12 as much as possible in order to improve the toner dischargeability.

  The toner collecting screw 15 is disposed near the bottom surface of the case 18 and sends out the toner collected by the brush roller 12 to a waste toner box (not shown) outside the case 18. A seal material is attached to the upstream side of the opening of the case 18 in the rotation direction of the photosensitive drum 1 so as to prevent the collected toner from leaking out of the case 18 again.

  Here, the brush roller 12 is characterized in that it has a plurality of brushing regions having different characteristics regarding the discharge of the toner collected from the photosensitive drum 1 and the removal and / or application of the solid lubricant 13. is there. That is, in this embodiment, the cleaning unit 7 has only one brush roller 12, but the portion of the brush roller 12 that contacts the surface of the photosensitive drum 1 has a plurality of brushing regions having different characteristics. Have. This configuration will be described in detail below.

  FIG. 1 is a top view showing a configuration of a brush roller (cleaning brush) 12 according to an embodiment of the present invention. As shown in FIG. 1, the brush roller 12 has a configuration in which a brush fabric (brush member) 22 is provided on the outer peripheral surface of a cylindrical shaft (base body) 23. The brush fabric 22 has two brushing regions 20a and 21a made of a plurality of hairs.

  FIG. 4 is an enlarged side view of a portion of the brush fabric 22 that includes the first brushing region 20a. FIG. 5 is an enlarged side view of a portion including the second brushing region 21 a in the brush fabric 22. FIG. 6 is a schematic diagram showing a state in which the first brushing region 20 a comes into contact with the solid lubricant 13. FIG. 7 is a schematic diagram showing a state where toner enters the first brushing area 20a. FIG. 8 is a schematic diagram showing a state in which the second brushing region 21 a comes into contact with the solid lubricant 13. FIG. 9 is a schematic diagram showing a state in which toner has entered the second brushing area 21a.

  Both the first brushing area 20a and the second brushing area 21a rub against the surfaces of the photosensitive drum 1 and the solid lubricant 13, and as shown in FIGS. There are a plurality of hairs on the bases 20b and 21b, but their characteristics are different. Specifically, the first brushing region 20a has thin and long hairs and the hair density is higher than that of the second brushing region 21a.

  As described above, the first brushing region 20a is supple because the hair is thin and long, and as shown in FIG. 6, the first brushing region 20a softly contacts the solid lubricant 13 such as soap and scrapes off the solid lubricant 13 little by little. be able to. Further, since the first brushing region 20 a has a high hair density, the shaved lubricant can be uniformly applied to the surface of the photosensitive drum 1. However, from the viewpoint of toner dischargeability, since the hair is long and the density of the hair is high, the toner is easily entangled with the hair as shown in FIG. . Further, since the hair is thin, the adhering toner is likely to aggregate, and the toner discharging property is not so good.

  On the other hand, since the second brushing region 21a has thick and short hairs, the hairs have high rigidity, and as shown in FIG. Ii) they tend to scrape off. Further, since the hair density is low, unevenness tends to occur when the shaved lubricant is uniformly applied to the surface of the photosensitive drum 1. Instead, from the viewpoint of toner dischargeability, since the hair is short and the density of the hair is low, as shown in FIG. 9, it has the advantage that the toner is not easily entangled with the hair and the toner is easily discharged. ing. Further, since the hair is thick, the adhered toner hardly aggregates, and the toner dischargeability is good.

  In the present embodiment, since the roles are shared by the first brushing area 20a and the second brushing area 21a having different characteristics, the solid lubricant 13 is uniformly applied to the photosensitive drum 1 while being scraped off little by little. In addition, the toner attached to the brush roller 12 from the photosensitive drum 1 can be effectively discharged. In other words, the first brushing region 20a mainly plays a role in scraping off the solid lubricant 13 and applying it to the photosensitive drum 1, while discharging the toner adhering to the brush roller 12 from the photosensitive drum 1. The second brushing area 21a mainly plays the role.

  In addition, instead of the configuration of the above-described embodiment, a method of providing a plurality of brush rollers having different characteristics is also conceivable. However, in this method, the number of members increases, and the cost increases. Since space is required, restrictions on the machine design are increased. Therefore, the configuration of this embodiment is more advantageous.

  The first brushing region 20a and the second brushing region 21a do not have to be different in all of the hair length, thickness, and density, and the hair length, hair thickness, hair hair It is sufficient that at least one of the density and the hair material is different. Note that it is also effective to change the material of the hair because the properties such as the stiffness of the hair change.

  Next, an example of a method for manufacturing the brush roller 12 described above will be described. FIG. 10 shows an embodiment of the present invention and is a top view showing the shape of the brush fabric 22 used for manufacturing the brush roller 12.

  First, a belt-like (rectangular) first brush fabric 22a having the first brushing region 20a and a belt-like second brush fabric 22b having a second brushing region 21a are prepared. The width (length in the short direction) of the brush fabrics 22a and 22b is determined so that the ratio thereof is the area ratio of the two brushing regions 20a and 21a in the brush roller 12.

  Then, as shown in FIG. 10, the first brush fabric 22a and the second brush fabric 22b are arranged so that the longitudinal directions of the first brush fabric 22a and the second brush fabric 22b are parallel to each other, and there is no gap between them. And Then, the brush fabric 22 is spirally wound around the outer peripheral surface of a metal shaft 23 such as SUS so that the brushing regions 20a and 21a face outward. At this time, the brush fabric 22 is wound without any gap so that the outer peripheral surface of the shaft 23 is not exposed. Moreover, you may stick the brush fabric 22 to the shaft 23 so that the shaft 23 and the brush fabric 22 may not shift.

  1 is manufactured, that is, on the outer peripheral surface of the shaft 23, the brush roller 12 in which the first brushing region 20a is spirally formed along the second brushing region 20b without gaps is manufactured. can do. In addition, according to this structure, since each brushing area | region 20a * 21a is located in a line with the circumferential direction on the outer peripheral surface of the shaft 23, all the area | regions of the peripheral surface of the photosensitive drum 1 are both brushing area | region 20a * 21a. Rubbed. Therefore, a region where the toner is not sufficiently removed or a region where unevenness is applied to the lubricant does not partially occur on the surface of the photosensitive drum 1.

  In the above-described embodiment, the brush roller 12 has two brushing regions, but may be three or more. In this case as well, it is preferable that each brushing region is formed in a spiral shape on the outer peripheral surface of the shaft 23 and that one brushing region is formed in a spiral shape along the other brushing region without a gap.

  In the above-described embodiment, a plurality of brushing regions having different characteristics are provided for the purpose of achieving both the toner discharging ability and the lubricant applying ability. However, the present invention is not limited to this. For example, two or more types of brushing regions having different conductivity and toner discharge performance may be provided in order to achieve both the charge removal performance and the toner discharge performance. In other words, by providing a plurality of brushing regions in which at least one of hair density, hair thickness, hair material, hair length, etc. is different from each other, both toner discharge ability and lubricant application ability are achieved. In addition, it is possible to achieve a variety of capabilities such as a neutralization capability and a toner discharge capability.

〔Example〕
Below, the experiment conducted in order to verify the effectiveness of this invention is demonstrated.

(Experiment 1)
In this experiment, whether the brush roller has only a single brushing area or a plurality of brushing areas with different hair densities, the ability to apply lubricant and the ability to discharge toner are determined. To see how they differ.

  In the following description, the unit “f” indicating the hair density is F, and indicates the number of hairs per square inch. The unit “d” indicating the thickness of the hair is denier.

  First, fabrics A, B, and C having hair densities of 15000f, 30000f, and 50000f were prepared as brush fabrics used for the brush roller. These fabrics A to C are the same except for the density of the hair, and are all made of nylon, and the thickness of the hair is 30d and the length is 2 mm.

  Then, as Comparative Example 1, a brush roller using only the fabric C was produced. Further, as Comparative Example 2, a brush roller using only the fabric B was produced. Further, as Comparative Example 3, a brush roller using only the fabric A was produced. Further, as Example 1, a brush roller using fabrics A, B, and C at a ratio of 30%, 30%, and 40%, respectively, was produced. As shown in FIG. 11, each of these brush rollers has a diameter of 6 mm and a length (width) of 380 mm on the peripheral surface of the SUS shaft 23 so that the length in the width direction is 315 mm. It was made by winding the dough.

  Next, these produced brush rollers were set in an image forming apparatus (AR705S manufactured by Sharp), and printing was continuously performed. Note that zinc stearate was used as the solid lubricant, and MX7000N manufactured by Sharp was used as the toner.

  The evaluation of the application performance of the lubricant is based on (1) whether or not the consumption amount of the lubricant per sheet is within an appropriate range (10 to 100 μg), and (2) whether there is no application unevenness. went. On the other hand, the toner discharging ability was evaluated based on the number of printed sheets until the toner accumulated on the brush roller and the cleaning failure occurred. Table 1 below summarizes the conditions and results of Comparative Examples 1 to 3 and Example 1.

  Although the brush roller of Comparative Example 1 had no problem in the ability to apply the lubricant, it was found that there was a problem in the toner discharging ability because a cleaning failure occurred with the number of printed sheets of 10,000. Further, the brush roller of Comparative Example 2 was found to have a slight problem in the toner discharge capability because of a slight unevenness in the application of the lubricant and a defective cleaning at the number of printed sheets of 10,000. In addition, the brush roller of Comparative Example 3 did not cause poor cleaning even when the number of printed sheets was 10,000. Therefore, although the toner discharging ability was sufficient, uneven application of the lubricant was clearly seen. On the other hand, since the brush roller of Example 1 did not cause cleaning failure even when the number of printed sheets was 10,000, the toner discharging ability was sufficient, and the lubricant application ability had no problem at all.

  From the above, it has been shown that by providing a plurality of brushing regions having different hair densities on the brush roller, it is possible to achieve both toner discharge ability and lubricant application ability.

(Experiment 2)
In this experiment, the ability to apply the lubricant and the ability to discharge the toner are different depending on whether the brush roller has only a single brushing area or a plurality of brushing areas having different hair lengths. We investigated how they differ.

  First, fabrics D, E, and F having hair lengths of 2 mm, 3 mm, and 5 mm were prepared as brush fabrics used for the brush roller. These fabrics D to F are the same except for the length of the hair, all are made of nylon, and the thickness of the hair is 30d and the density is 30000f.

  Then, as Comparative Example 4, a brush roller using only the fabric F was produced. Further, as Comparative Example 5, a brush roller using only the fabric E was produced. Further, as Comparative Example 6, a brush roller using only the fabric D was produced. Further, as Example 2, a brush roller using fabrics D, E, and F at a ratio of 30%, 30%, and 40%, respectively, was produced.

  Next, with respect to these produced brush rollers, the lubricant application ability and the toner discharge ability were evaluated in the same manner as in Experiment 1 described above. Table 2 below summarizes the conditions and results of Comparative Examples 4 to 6 and Example 2.

  Although the brush roller of Comparative Example 4 had no problem in the ability to apply the lubricant, it was found that there was a problem in the toner discharge ability because a cleaning failure occurred when the number of printed sheets was 10,000. In addition, the brush roller of Comparative Example 5 had a lubricant application amount of 40 μg / sheet, slightly exceeding the appropriate range, and caused poor cleaning with 10,000 printed sheets. I found out there was a problem. In addition, although the brush roller of Comparative Example 6 did not cause poor cleaning even when the number of printed sheets was 10,000, the toner discharging ability was sufficient, but the amount of lubricant applied was 60 μg / sheet, greatly increasing the appropriate range. Exceeded. On the other hand, since the brush roller of Example 2 did not cause poor cleaning even when the number of printed sheets was 10,000, the toner discharging ability was sufficient, and the lubricant application ability had no problem at all.

  From the above, it has been shown that by providing a plurality of brushing regions having different hair lengths on the brush roller, it is possible to achieve both toner discharge capability and lubricant application capability.

(Experiment 3)
In this experiment, the ability to apply the lubricant and the ability to discharge the toner are different depending on whether the brush roller has only a single brushing area or a plurality of brushing areas having different hair thicknesses. We investigated how they differ.

  First, fabrics G, H, and I having hair thicknesses of 30d, 15d, and 3d were prepared as brush fabrics used for the brush roller. These fabrics G to I are the same except for the thickness of the hair, all are made of nylon, the length of the hair is 2 mm, and the density is 30000f.

  Then, as Comparative Example 7, a brush roller using only the fabric I was produced. Further, as Comparative Example 8, a brush roller using only the fabric H was produced. Further, as Comparative Example 9, a brush roller using only the fabric G was produced. Further, as Example 3, a brush roller using fabrics G, H, and I at a ratio of 30%, 30%, and 40%, respectively, was manufactured.

  Next, with respect to these produced brush rollers, the lubricant application ability and the toner discharge ability were evaluated in the same manner as in Experiment 1 described above. Table 3 below summarizes the conditions and results of Comparative Examples 7 to 9 and Example 3.

  Although the brush roller of Comparative Example 7 had no problem in the ability to apply the lubricant, it was found that there was a problem in the toner discharging ability because a cleaning failure occurred when the number of printed sheets was 10,000. In addition, the brush roller of Comparative Example 8 had a lubricant application amount of 40 μg / sheet, slightly exceeding the appropriate range, and caused poor cleaning with 10,000 printed sheets. I found out there was a problem. In addition, the brush roller of Comparative Example 9 did not cause poor cleaning even when the number of printed sheets was 10,000, so the toner discharging ability was sufficient, but the amount of lubricant applied was 60 μg / sheet, greatly increasing the appropriate range. Exceeded. On the other hand, since the brush roller of Example 3 did not cause a cleaning failure even when the number of printed sheets was 10,000, the toner discharging ability was sufficient, and the lubricant application ability had no problem at all.

  From the above, it has been shown that by providing a plurality of brushing regions having different hair thicknesses on the brush roller, it is possible to achieve both toner discharge ability and lubricant application ability.

  In addition, when the hair of the brush roller is thick, there is an advantage that the toners hardly aggregate. Once the toner starts to aggregate, it becomes clogged, so it is considered that a brush with thick hair has better toner discharge than a brush with thin hair.

(Experiment 4)
In this experiment, whether the brush roller has only a single brushing area or a plurality of brushing areas with different bristle materials, the lubricant application ability and the toner discharge ability are determined. To see how they differ.

  First, fabrics J, K, and L made of acrylic, nylon, and polyester were prepared as brush fabrics used for the brush roller. These fabrics J to L are the same except for the hair material, and all have a hair thickness of 15d, a length of 3mm, and a density of 30000f.

  Then, as Comparative Example 10, a brush roller using only the fabric L was produced. Further, as Comparative Example 11, a brush roller using only the fabric K was produced. Further, as Comparative Example 12, a brush roller using only the fabric J was produced. Further, as Example 4, a brush roller using fabrics J, K, and L at a ratio of 30%, 30%, and 40%, respectively, was produced.

  Next, with respect to these produced brush rollers, the lubricant application ability and the toner discharge ability were evaluated in the same manner as in Experiment 1 described above. Table 4 below summarizes the conditions and results of Comparative Examples 10 to 12 and Example 4.

  The brush roller of Comparative Example 10 had a lubricant application amount of 40 μg / sheet, slightly exceeding the appropriate range, and caused a defective cleaning when the number of printed sheets was 10,000. I found out. In addition, although the brush roller of Comparative Example 11 did not cause cleaning failure even when the number of printed sheets was 10,000, the toner discharging ability was sufficient, but the amount of lubricant applied was 60 μg / sheet, greatly increasing the appropriate range. Exceeded. Further, although the brush roller of Comparative Example 10 had no problem in the ability to apply the lubricant, it was found that there was a problem in the toner discharging ability because the cleaning failure occurred at the number of printed sheets of 10,000. On the other hand, since the brush roller of Example 4 did not cause a cleaning failure even when the number of printed sheets was 10,000, the toner discharging ability was sufficient, and the lubricant application ability had no problem at all.

  From the above, it has been shown that by providing a brush roller with a plurality of brushing regions having different hair materials, it is possible to achieve both toner discharge capability and lubricant application capability.

  From Experiments 1 to 4 described above, even if a problem occurs only with a single brushing area, it is possible to achieve both toner discharge ability and lubricant application ability by combining a plurality of brushing areas having different characteristics. It has been shown.

(Experiment 5)
In this experiment, how the lubricant application ability and the toner discharge ability differ for brush rollers with various ratios of two brushing areas with different hair thickness, length, density, and material. I investigated.

  First, as the brush fabric used for the brush roller, the hair thickness is 30d, the length is 2mm, the density is 15000f, the material is nylon fabric M, the hair thickness is 3d, the length is 5mm, the density is 50000f, A material N of acrylic material was prepared.

  Then, as Comparative Examples 13, 14, 15, and 16, brush rollers were produced using these brush fabrics M and N in the ratios of 100: 0, 80:20, 20:80, and 0: 100, respectively. Further, as Examples 5, 6, and 7, brush rollers using brush fabrics M and N at a ratio of 70:30, 50:50, and 30:70, respectively, were produced.

  Next, with respect to these produced brush rollers, the lubricant application ability and the toner discharge ability were evaluated in the same manner as in Experiment 1 described above. Table 5 below summarizes the conditions and results of Comparative Examples 13 to 16 and Examples 5 to 7.

  The brush roller of Comparative Example 13 could not apply the lubricant. Further, the brush roller of Comparative Example 14 could not apply the lubricant stably and sufficiently. Further, the brush roller of Comparative Example 15 did not have sufficient toner discharge capability. Further, the brush roller of Comparative Example 16 did not have the ability to discharge toner. On the other hand, the brush rollers of Examples 5 to 7 were good in both lubricant application ability and toner discharge ability.

  From this experimental result, it was shown that even when two brushing regions were provided, if the ratio of one of them was too large, the function of the other could not be fully exerted, causing problems. From the above experiment, it was found that the area ratio of the two brushing regions is preferably in the range of 30:70 to 70:30.

  The present invention is not limited to the above-described embodiments and examples, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope of the claims are also included in the technical scope of the present invention.

  In addition, it goes without saying that the present invention includes a numerical range other than the numerical range shown in the present specification as long as it is within a reasonable range that does not contradict the gist of the present invention.

  According to the present invention, a cleaning brush capable of achieving both effective toner removal and appropriate lubricant application is provided. Therefore, the present invention can be suitably applied to a multifunction machine or printer using an electrophotographic system. Can do.

1 is a top view illustrating a configuration of a brush roller (cleaning brush) according to an embodiment of the present invention. FIG. 3 is a longitudinal sectional view of the image forming apparatus viewed from the front side. It is an expanded sectional view which shows the structure of a cleaning unit. It is an expanded side view of the location including the 1st brushing area | region among brush cloth. It is an expanded side view of the location including the 2nd brushing area | region among brush cloth. It is a schematic diagram which shows a mode that a 1st brushing area | region contacts a solid lubricant. FIG. 6 is a schematic diagram illustrating a state in which toner enters a first brushing area. It is a schematic diagram which shows a mode that a 2nd brushing area | region contacts a solid lubricant. FIG. 6 is a schematic diagram illustrating a state in which toner enters a second brushing area. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention and is a top view illustrating a shape of a brush fabric used for manufacturing a brush roller. It is a top view which shows a prior art and shows the shape of the brush fabric used for manufacture of a brush roller. It is a side view which shows a prior art and shows the structure of a brush roller. It is an expansion side surface of the brush fabric shown in FIG. Fig. 13 is an enlarged side view of the brush fabric shown in Fig. 12.

Explanation of symbols

1 Photoconductor drum (photoconductor)
2 Charging unit 3 Exposure unit 4 Development unit 5 Transfer unit 6 Fixing unit 7 Cleaning unit 10 Image forming apparatus 11 Blade 12 Brush roller (cleaning brush)
13 Solid lubricant 15 Toner recovery screw 16 Flicker 17 Lubricant holding member 18 Case 20a First brushing area 21a Second brushing area 22 Brush fabric 23 Shaft

Claims (12)

A cleaning brush provided with a brush member that slides in contact with the photoreceptor and collects the toner adhering to the photoreceptor from the photoreceptor,
The brush member has a plurality of brushing regions that slide in contact with the photoreceptor,
The cleaning brush, wherein the plurality of brushing regions are different from each other in at least one of hair density, hair thickness, hair material, and hair length. A cleaning brush provided with a brush member that slides in contact with the photosensitive member and the solid lubricant, scrapes off the solid lubricant, applies the toner to the photosensitive member, and collects toner adhering to the photosensitive member from the photosensitive member; There,
The brush member has a plurality of brushing regions that slide in contact with the photoreceptor and the solid lubricant,
The cleaning brush characterized in that the plurality of brushing regions have different characteristics in terms of discharging the toner collected from the photoconductor to the outside of the brushing region and scraping and / or applying the solid lubricant.   The cleaning brush according to claim 2, wherein the plurality of brushing regions have at least different hair densities.   The cleaning brush according to claim 2, wherein the plurality of brushing regions have at least different hair thicknesses.   The cleaning brush according to claim 2, wherein the plurality of brushing regions have at least different hair materials.   The cleaning brush according to claim 2, wherein the plurality of brushing regions have at least different hair lengths. Further comprising a rotatable cylindrical base body,
The brush member is provided on the outer peripheral surface of the base,
2. Each brushing region is formed in a spiral around the outer peripheral surface of the substrate, and one brushing region is formed in a spiral along the other brushing region. 2. The cleaning brush according to 2.   8. The cleaning brush according to claim 7, wherein the brush member comprises a plurality of brush fabrics, and each brush fabric has the brushing regions having different characteristics.   3. The cleaning brush according to claim 1, wherein the plurality of brushing regions include a first brushing region and a second brushing region having different characteristics from each other.   10. The cleaning brush according to claim 9, wherein an area ratio between the first brushing region and the second brushing region is in a range of 30:70 to 70:30.   The said 1st brushing area | region and the 2nd brushing area | region differ in at least 2 of the density of the hair, the thickness of the hair, the material of the hair, and the length of the hair. The cleaning brush described. The cleaning brush according to claim 1 or 2,
An image forming apparatus comprising the photosensitive member.

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