JP3861492B2 - Paper dust removing device for image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a paper dust of an image forming apparatus that contacts a photoreceptor or an intermediate transfer body that carries and conveys a toner image to a transfer position on a transfer medium such as paper and removes the paper dust on the photoreceptor or the intermediate transfer body. The present invention relates to a removing device.
[0002]
[Prior art]
  In an electrophotographic image forming apparatus that forms an image by transferring a toner image on a photoconductor or an intermediate transfer body to paper, without scraping the transfer residual toner on the photoconductor or the intermediate transfer body with a blade or the like, There is a so-called cleaner-less development method in which the developer is collected and reused. In such a system, paper dust from the paper is also collected by the developing device, and printing defects due to the paper dust have occurred. Therefore, in this type of image forming apparatus, a method of providing a paper dust removing device between the transfer device and the developing device has been proposed.
[0003]
[Problems to be solved by the invention]
  As this paper dust removing device, (1) a rotary brush roller, (2) a rotary brush roller in which brush fibers are formed in a loop shape (see Japanese Patent Laid-Open No. 1-116677), (3) the surface of a rubber roller A rotating nonwoven fabric roller (see Japanese Utility Model Laid-Open No. 62-181973), which is coated with a nonwoven fabric, has been proposed. However, these devices (1) to (3) have the following problems.
[0004]
  In the apparatus of (1) or (2), the fibers contained in the paper powder could be removed well, but when acidic paper was used as the transfer medium, the filler such as talc contained in the acidic paper was The brush cannot be removed sufficiently, and as a result, there is a problem that an image defect such as fogging on a white background is caused due to talc mixed in the developing device.
[0005]
  In the apparatus (3), the nonwoven fabric is strongly pressed (pressed) against the photoreceptor. Therefore, fillers such as talc can also be captured, but the nonwoven fabric rubs paper dust against the photoconductor, so that soft talc is stretched and filming occurs on the surface of the photoconductor. It had the problem of decreasing.
[0006]
  The present invention has been made in view of these problems, and even when acidic paper is used as a transfer medium, paper dust made of fillers such as fibers and talc is satisfactorily produced without causing filming on the photoreceptor. An object of the present invention is to provide a paper dust removing device for an image forming apparatus that can be removed.
[0007]
[Means for Solving the Problems and Effects of the Invention]
  In order to achieve this object, the invention according to claim 1 is characterized in that the electrostatic latent image formed on the photoreceptor is developed with a developer to form a visible image, and the visible image is transferred to paper or the like. In an image forming apparatus that forms an image on a transfer medium by transferring the image to a medium, the paper dust removing apparatus removes paper powder from a visible image carrier that carries and conveys the visible image to a transfer position of the image. The base material is formed in the vicinity of a movement path of the visible image carrier at a predetermined interval from the visible image carrier, and is formed into a sheet shape from a nonwoven fabric, a woven fabric, or a knitted fabric. And a contact member that is partly in contact with the visible image carrier, and a contact portion of the contact member with the visible image carrier is separated from the substrate.In addition, The contact member has one end fixed to the substrate and the other end in contact with the visible image carrier.It is characterized by that.
[0008]
  According to the paper dust removing device of the image forming apparatus of the present invention (Claim 1), the contact member is formed in a sheet shape with a nonwoven fabric, a woven fabric or a knitted fabric, and is arranged at a predetermined interval from the visible image carrier. Since the contact member is supported by the base material and a part thereof contacts the visible image carrier, and the contact portion is away from the base material, the contact member is boosted by the base material and strongly against the visible image carrier. There is no pressing (pressure contact). Accordingly, both the fiber component and the filler component of the paper powder can be satisfactorily removed by the entangled fibers constituting the contact member. In addition, since the pressing force when the contact member comes into contact with the visible image carrier can be significantly reduced, the photoreceptor is generated when the contact member strongly rubs the photoreceptor with a filler such as talc contained in the paper powder. The above filming can be prevented. Further, the contact member is not strongly pressed against the visible image carrier to damage the surface of the visible image carrier.
[0009]
  Also,One end of the contact member is fixed to the substrate, and the other end that is not fixed contacts the visible image carrier, so that the contact member alone makes soft contact with the surface of the visible image carrier. For this reason, it is possible to significantly reduce the pressing force when one end of the contact member that is not fixed contacts the visible image carrier. Therefore, paper dust can be removed satisfactorily and the occurrence of filming can be prevented.
[0010]
[0011]
[0012]
  Next, the claim2In the described invention, the substrate rotates about an axis orthogonal to the moving direction of the visible image carrier, and the contact member contacts the visible image carrier by the rotation of the substrate. It is characterized by.
  Thus, the claim2According to the paper dust removing device of the image forming apparatus described, the substrate rotates about an axis orthogonal to the moving direction of the visible image carrier, and the contact member rotates the visible image carrier by the rotation of the substrate. Therefore, the location where the contact member contacts the visible image carrier moves one after another. Therefore, the removed paper dust is not accumulated on the contact member, and thereby the surface of the visible image carrier can be prevented from being damaged.
[0013]
  Next, the claim3In the described invention, the electrostatic latent image formed on the photosensitive member is developed with a developer to form a visible image, and the visible image is transferred to a transfer medium such as paper, whereby the image is transferred to the transfer medium. A paper dust removing device for removing paper dust from a visible image carrier that carries and conveys the visible image to a transfer position of the image, the moving path of the visible image carrier A contact made in the vicinity of a base material disposed at a predetermined interval from the visible image carrier and a nonwoven fabric, a woven fabric or a knitted fabric, and is in contact with a part of the visible image carrier supported by the base material And the base material is disposed at a position higher than the position where the contact member contacts the visible image carrier, and the contact member hangs down from the base material due to gravity. Contact the carrierFurther, one end of the contact member is fixed to the base material and the other end is suspended by gravity, thereby contacting the visible image carrier.It is characterized by doing.
[0014]
  Thus, the claim3According to the paper dust removing device of the image forming apparatus described, the base material disposed at a predetermined interval from the visible image carrier is disposed at a position higher than the position where the contact member contacts the visible image carrier. And supporting the contact member. For this reason, if the contact member hangs down from the substrate by its own weight and comes into contact with the visible image carrier, the contact member comes into contact with the visible image carrier by gravity, and the contact member is pushed. The pressure can be significantly reduced. Therefore, the paper dust can be satisfactorily removed by the entangled fibers, and filming on the photoreceptor can be prevented.
[0015]
  Also,Since the end of the contact member that is not fixed to the base material hangs down due to gravity, the contact member can be brought into contact with the visible image carrier by its own weight, and the pressing force at the time of contact can be significantly reduced. . Therefore, paper dust can be removed satisfactorily and the occurrence of filming can be prevented.
[0016]
[0017]
[0018]
  Next, the claim4The described invention is characterized in that the contact member is formed in a sheet shape.
  Thus, the claim4According to the paper dust removing device of the image forming apparatus described, since the contact member is formed in a sheet shape, the contact area with the surface of the rotating visible image carrier can be widened. It can be removed efficiently. Moreover, since it has a certain thickness, it is excellent in durability as a contact member, and it is easy to carry out processing such as cutting and pasting according to the size of the visible image carrier.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
  FIG. 1 is a cross-sectional view illustrating a schematic configuration of a laser beam printer 1 including a paper dust removing device 80 to which the present invention is applied.
[0020]
  In FIG. 1, a laser beam printer 1 includes a feeder unit 10 that feeds a sheet P as a transfer medium at the bottom of a main body case 2.
  The feeder unit 10 includes a paper pressing plate 11, a compression spring 12, and a paper feeding roller 13. The paper P is sandwiched between the paper pressing plate 11 and the paper feeding roller 13, and the uppermost layer is placed at a predetermined timing. The paper P is supplied.
[0021]
  A pair of registration rollers 14 and 15 are rotatably supported on the downstream side of the sheet feeding roller 13 in the conveying direction indicated by an arrow A, and a transfer position formed by a photosensitive drum 20 and a transfer roller 60 described later. The paper P is conveyed at a predetermined timing. The photosensitive drum 20 as a photosensitive member and a visible image carrier has a positively chargeable material, for example, an organic photosensitive member whose main component is a positively charged polycarbonate. Specifically, the photosensitive drum 20 is a light having a predetermined thickness (for example, about 20 μm) in which a photoconductive resin is dispersed in polycarbonate on the outer periphery of a cylindrical cylindrical sleeve made of aluminum, for example. A hollow drum having a conductive layer is formed, and is pivotally supported by the main body case 2 in a state where the cylindrical sleeve is grounded. Further, the photosensitive drum 20 is rotationally driven in the direction of arrow B by a driving unit (not shown).
[0022]
  Further, a charger 30 for charging the photosensitive drum 20 and a laser for irradiating the charged photosensitive drum 20 with a laser beam L for forming an electrostatic latent image are provided around the photosensitive drum 20 in the rotation direction. A scanner unit 40, a developing device 50 that develops the formed electrostatic latent image with toner to form a toner image (visible image), and a transfer roller 60 that transfers the formed toner image onto the paper P are sequentially arranged. ing. The paper dust removing device 80 of the present invention is disposed upstream of the charger 30 and downstream of the transfer roller 60 in the rotational direction of the photosensitive drum 20 indicated by arrow B.
[0023]
  Here, the charger 30 is composed of, for example, a scorotron charger for positive charging that generates corona discharge from a charging wire made of tungsten or the like. The laser scanner unit 40 includes a laser generator (not shown) that generates a laser beam L for forming an electrostatic latent image on the photosensitive drum 20, a polygon mirror (pentahedral mirror) 41 that is driven to rotate, and a pair of The lens 42 and 43 and a pair of reflecting mirrors 44 and 45 are included.
[0024]
  In the developing device 50, a toner storage chamber 52 is formed in a main body 51, and an agitator 53 and a toner 54 as a positively chargeable nonmagnetic one-component developer having electrical insulation are stored in the toner storage chamber 52. Is done. A developing chamber 55 is formed on the side adjacent to the toner storage chamber 52, and a supply roller 56 and a developing roller 57 are rotatably supported. The toner 54 on the developing roller 57 is regulated to a predetermined layer thickness by the layer thickness regulating blade 58 and used for development. The layer thickness regulating blade 58 is formed by integrally forming a contact portion made of a rubber member such as silicon rubber on an end portion of a plate spring made of stainless steel (SUS) or the like. As a result, the contact portion is pressed against the photosensitive drum 20.
[0025]
  The transfer roller 60 is rotatably supported and is made of a foamed elastic body having conductivity, such as silicon rubber or urethane rubber. Then, when the paper P passes through the transfer position where the transfer roller 60 and the photosensitive drum 20 face each other, a transfer bias is applied to the transfer roller 60 so that the toner image on the photosensitive drum 20 is transferred to the paper P. .
[0026]
  Further, on the downstream side of the transfer position of the paper P from the transfer position (indicated by an arrow A in FIG. 1), a fixing unit 70 for fixing the toner image on the paper P, a pair of paper transport rollers 73 and a paper discharge A roller 74 and a paper discharge tray 75 are provided.
  The fixing unit 70 includes a heating roller 71 and a pressing roller 72, and fixes the toner image transferred onto the paper P by pressing between the rollers 71 and 72 while being heated by the heating roller 71.
[0027]
  In the transport direction of the paper P, the transport roller 73 and the paper discharge roller 74 are provided on the downstream side of the fixing unit 70, and the paper discharge tray 75 is provided on the downstream side of the paper discharge roller 74.
  In the laser beam printer 1 provided with the paper dust removing device 80 of the present embodiment as described above, the surface of the photosensitive drum 20 is uniformly charged by the charger 30 and modulated by the laser scanner unit 40 according to the image information. When the light L is irradiated, an electrostatic latent image is formed on the surface of the photosensitive drum 20.
[0028]
  The electrostatic latent image is visualized with toner 54 by the developing device 50, and the visible image formed on the photosensitive drum 20 is conveyed to the transfer position by the photosensitive drum 20.
  At the transfer position, the paper P is supplied via the feeder unit 10 and the registration rollers 14 and 15, and the visible image is transferred to the paper P by a transfer bias applied to the transfer roller 60.
[0029]
  Next, the paper P is conveyed to the fixing unit 70 and is nipped and conveyed by the heating roller 71 and the pressing roller 72 of the fixing unit 70, and the visible image on the paper P is pressurized and heated to be fixed on the paper P. Is done.
  Then, the paper P is discharged to a paper discharge tray 75 above the laser beam printer 1 by a pair of transport rollers 73 and paper discharge rollers 74, and the image forming operation is completed.
[0030]
  On the other hand, the toner remaining on the photosensitive drum 20 after the transfer is collected by the developing roller 57 of the developing device 50 and again used for development.
  As described above, the laser beam printer 1 including the paper dust removing device 80 of the present embodiment employs a so-called cleaner-less developing method. Therefore, since a waste toner storage container for scraping and storing the toner remaining on the photosensitive drum 20 is not required, the apparatus can be reduced in size and the toner can be effectively used.
[0031]
  However, conventionally, when the cleaner-less development method is adopted, the paper dust adhering to the surface of the photosensitive drum 20 at the time of transfer is collected by the developing device 50 together with the toner remaining on the photosensitive drum 20 to cause an image defect. There was a thing.
  Here, the relationship between paper dust and image defects will be described in detail.
[0032]
  In addition to pulp fibers (cellulose extracted from hardwoods and conifers), the paper powder contains fillers that make the paper opaque and white, internal sizing agents to prevent ink bleeding, and sizing agents Contains an internally added size fixing agent that adsorbs to the pulp fiber. In addition, talc or clay is mainly used for the acidic paper, rosin sizing agent is used for the internal sizing agent, and sulfuric acid band (aluminum sulfate) is used for the internal sizing fixing agent.
[0033]
  Among them, substances that particularly adversely affect the electrophotographic process are pulp fibers and filler talc. When pulp fibers are mixed in a developing device using a non-magnetic one-component developer, the pulp fibers may be sandwiched between the layer thickness regulating blade and the developing roller and damage the layer thickness regulating blade or the developing roller.
[0034]
  Furthermore, when the pulp fiber passes through the layer thickness regulating blade together with the toner clinging to the pulp fiber, adheres to the paper P, and is discharged through the fixing process as it is, particularly when it adheres to the white solid portion. Will be recognized by the naked eye as prominent garbage.
[0035]
  On the other hand, talc is a very strong negatively chargeable substance. In a process using positively charged toner, if it is mixed in the developing device, the charge amount of the toner is reduced and print fogging is caused.
  Furthermore, even in a process using negatively charged toner, it causes print fogging similarly, or even if it does not become fogging, the charge amount of the toner becomes too high and the image density is lowered. There is.
[0036]
  In order to remove such paper dust, conventionally, a paper dust removing device using a rotating brush or a non-woven fabric is brought into contact with the photosensitive drum, but the paper dust removing device is simply exposed to light. The paper dust cannot be sufficiently captured only by contacting the drum, and the above-described problems have not been solved. In particular, when acid paper is used as paper, fogging occurs when a small amount of talc contained in the acid paper is mixed in the developing device, so that such a problem has occurred remarkably.
[0037]
  However, in order to increase the paper dust removal capability of such a paper dust removing device, when the paper dust removing device is strongly pressed (pressed) against the photosensitive drum, the captured hard pulp fiber damages the surface of the photosensitive drum. There was a problem.
  Further, when the filler is accumulated in the paper dust removing member, the soft filler is rubbed between the photosensitive drum surface and the paper dust removing device or between the photosensitive drum surface and the pulp fiber accumulated in the paper dust removing device. In the meantime, the filler is thinly adhered to the surface of the photosensitive drum, and a phenomenon called filming occurs. When filming occurs, the charging potential on the surface of the photosensitive drum before exposure and the potential after exposure change, so that proper image formation cannot be performed, or toner releasability is deteriorated, resulting in transfer failure. was there.
[0038]
  Therefore, in the present embodiment, in order to solve the above-described problems, the paper dust can be satisfactorily removed by forming a non-woven fabric, a woven fabric, a knitted fabric, etc. into a sheet shape and configuring the paper dust removing device. ing.
  The configuration of the paper dust removing device of the image forming apparatus according to the present embodiment will be described in detail below.
[0039]
  As shown in FIG. 2A, the paper dust removing device 80 of the present embodiment disposed in the vicinity of the movement path of the photosensitive drum 20 includes a case 82 having an insulating brush 81 inside, and a roller shaft 84. It is comprised by the resin-made rollers 86 as a base material integrally molded, and the nonwoven fabric sheet 88 as a contact member.
[0040]
  Here, one end of a nonwoven fabric sheet 88 impregnated with an oil agent is fixed to a plurality of flat sticking portions formed on the surface of the resin roller 86 with an adhesive, a double-sided tape, or the like. The nonwoven fabric sheet 88 is arranged so as to hang down due to gravity and to contact the photosensitive drum 20.
[0041]
  The resin roller 86 is rotated at a peripheral speed faster than the peripheral speed of the photosensitive drum 20 in a direction (indicated by an arrow C) opposite to the rotational direction of the photosensitive drum 20 (indicated by an arrow B).
  In addition, a storage space for scraping and collecting paper dust and toner adhering to the nonwoven fabric sheet 88 with the brush 81 is formed in the lower part inside the case 82.
[0042]
  Moreover, the nonwoven fabric sheet 88 uses what was integrated when the constituent fiber was entangled. This is because it is preferable to use a constituent fiber having a high degree of freedom in capturing fine paper dust between the fibers. As the constituent material, for example, synthetic fibers such as polyester fibers, polyamide fibers, polyolefin fibers, acrylic fibers, or composite fibers using resins of these fibers, semi-synthetic fibers such as acetate fibers, Alternatively, recycled fibers such as cupra and rayon, natural fibers such as cotton, hemp, and wool, or fiber members such as mixed cotton are used.
[0043]
  Moreover, as the oil agent impregnated into the nonwoven fabric sheet 88 as described above, one containing at least one or more of mineral oil, synthetic oil, silicone oil and surfactant is used. As the mineral oil, paraffinic hydrocarbons, naphthenic hydrocarbons, aromatic hydrocarbons and the like are used. Further, as the synthetic oil, alkylbenzene oil, polyolefin oil, polyglycol oil or the like is used. Further, as the silicone oil, linear dimethylpolysiloxane, cyclic dimethylpolysiloxane, methylhydrogen polysiloxane, various modified silicones, and the like are used. In addition, the surfactant is preferably a quaternary ammonium salt type as a cation type, and examples of the nonionic type include a polyethylene glycol type or a polyhydric alcohol type.
  In this embodiment, such an oil agent is supported at a ratio of 1 to 20% with respect to the weight of the nonwoven fabric sheet 88.
[0044]
  In the paper dust removing device 80 of the present embodiment configured as described above, the resin roller 86 as the base material is spaced from the photosensitive drum 20 and the position where the nonwoven fabric sheet 88 contacts the photosensitive drum 20. Are arranged so as to be in a high position.
  By doing so, the nonwoven fabric sheet 88 comes into contact with the photosensitive drum 20 by its own weight, and is not pressed against the photosensitive drum 20 by the resin roller 86 as a base material, so that the pressing force at the time of contact is significantly reduced. Can do. Therefore, paper dust can be removed satisfactorily and the occurrence of filming can be prevented.
[0045]
  Further, since the resin roller 86 as the base material is driven to rotate, the portions of the nonwoven fabric sheet 88 that come into contact with the photosensitive drum 20 move one after another. Therefore, the removed paper dust is not concentrated and accumulated at a specific portion of the nonwoven fabric sheet 88, and the surface of the photosensitive drum 20 can be prevented from being damaged by the paper dust.
[0046]
  In this embodiment, the nonwoven fabric sheet 88 can be brought into contact with the photosensitive drum 20 by centrifugal force by rotating the resin roller 86 as a base material at a higher speed.
  Moreover, since the nonwoven fabric sheet 88 is impregnated with the oil agent as described above, the paper dust can be satisfactorily removed by the cohesive force of the oil agent. In particular, even when acidic paper is used as the paper P, paper components (particularly talc) can be removed, and image defects such as fog can be prevented well.
[0047]
  Furthermore, according to this embodiment, since the pressing force of the nonwoven fabric sheet 88 against the photosensitive drum 20 is remarkably small, the transfer amount of the oil to the photosensitive drum 20 can be minimized. For this reason, a large amount of oil does not adhere to the photosensitive drum 20, and filming due to the oil can be prevented.
[0048]
  Further, since the paper dust removing device 80 is provided in the image forming apparatus of the cleanerless developing system in which the transfer residual developer is collected by the developing device and again used for development, when the transfer residual developer is collected by the developing device. In addition, it is possible to satisfactorily prevent paper dust from being mixed into the developing device.
[0049]
  Therefore, according to the paper dust removing device 80 of the present embodiment, the paper dust adhering to the photosensitive drum 20 is satisfactorily removed without causing filming, and the paper dust (pulp fiber or talc) developing device 50 is removed. Can be prevented. Therefore, it is possible to satisfactorily prevent image defects such as fogging caused by transfer of pulp fibers to the paper P and talc.
[0050]
  Further, the resin roller 86 as the base material is configured to rotate, and a storage space for the scraping brush 81 and the case 82 is formed in the lower portion thereof, so that the paper removed by the nonwoven fabric sheet 88 is formed. The powder is scraped off by the brush 81 and falls into the storage space of the case 82. Therefore, paper dust is not accumulated on the nonwoven fabric sheet 88, the surface of the photosensitive drum 20 is not damaged by hard paper dust (pulp fiber), and filming due to soft paper dust (talc) is good. Can be prevented.
[0051]
  (Other embodiment of paper dust removing device)
  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various aspect can be taken.
  The paper dust removing device 80 of this embodiment (see FIG. 2A) is a gravity that bonds and fixes one end of a non-woven fabric sheet 88 on a resin roller 86 as a base and works the other end on the non-woven fabric sheet 88. Although the example in which the photosensitive drum 20 is brought into contact with the photosensitive drum 20 by centrifugal force has been described, it is not always necessary to rotate the base material, and one end of the nonwoven fabric sheet 88 is bonded and fixed to the base material arranged in a fixed manner, and is not fixed. The other end may be hung down to contact the photosensitive drum 20. If it does in this way, the nonwoven fabric sheet 88 can be made to contact the photosensitive drum 20 only by gravity, and the pressing force at the time of contact can be reduced significantly. Therefore, the same paper dust removing effect as that of the present embodiment can be achieved.
[0052]
  Moreover, it can also be set as a structure as shown in FIG.2 (b). The paper dust removing device 90 shown in FIG. 2B is used by adhering and fixing a nonwoven fabric sheet 98 impregnated with an oil agent as a contact member to both ends of a support plate 95 as a base material. The paper dust removing device 90 configured as described above is arranged at any position toward the photosensitive drum 20 as long as the intermediate portion of the nonwoven fabric sheet 98 is in contact with the photosensitive drum 20 without contacting the support plate 95. May be. That is, when arranged above the photosensitive drum 20, the non-fixed non-woven fabric sheet 98 is brought into contact with the photosensitive drum 20 at an intermediate portion depending on gravity. Further, when the sheet is disposed on the lower side or on the side, the nonwoven fabric sheet 98 is thickened to have a waist, and is brought into contact with the photosensitive drum 20 at the warped intermediate part. In this way, since the intermediate portion of the nonwoven fabric sheet 98 does not contact the support plate 95, it can be brought into contact with the photosensitive drum 20 with a weak pressing force without being pushed back by the support plate 95. Therefore, the paper dust removing effect equivalent to that of the paper dust removing device 80 of the present embodiment can be achieved.
[0053]
  Moreover, it can also be set as a structure as shown in FIG.2 (c). A paper dust removing device 100 shown in FIG. 2C includes an elastic roller 106 as a base material on a case 102 having an insulative brush 101 inside, and a metal roller shaft 104 formed of aluminum or the like. Is formed with a sponge or the like. Furthermore, the elastic body roller 106 is formed in an endless shape having an inner periphery larger than the outer periphery, and a nonwoven fabric sheet 108 impregnated with an oil is placed around the elastic body roller 106. The elastic roller 106 rotates at a low speed in the same direction (indicated by arrow D) as the rotational direction of the photosensitive drum 20 (indicated by arrow B). In addition, a storage space for scraping and collecting paper dust and toner adhering to the nonwoven fabric sheet 108 with the brush 101 is formed in the lower part inside the case 102.
[0054]
  Since the inner periphery of the nonwoven fabric sheet 108 is formed in an endless shape in which the inner periphery of the nonwoven fabric sheet 108 is larger than the outer periphery of the elastic roller 106, a part of the inner peripheral surface of the nonwoven fabric sheet 108 is Supported by the outer peripheral surface of the elastic roller 106, the nonwoven fabric sheet 108 hangs down below the elastic roller 106 due to gravity. In addition, since the elastic roller 106 rotates in the same direction as the photosensitive drum 20, the nonwoven fabric sheet 108 is bent when approaching the surface of the photosensitive drum 20 and does not come into contact with the elastic roller 106. Can be brought into contact with the photosensitive drum 20.
[0055]
  As shown in FIG. 3, in the conventional paper dust removing device 120, the nonwoven fabric sheet 128 is bonded to the elastic body roller 126 with an adhesive or a double-sided tape without any gap, so that the nonwoven fabric sheet 128 contacts the photosensitive drum 20. At this time, the elastic roller 126 is pushed back and strongly presses against the photosensitive drum 20. Therefore, the occurrence of filming could not be prevented by rubbing paper dust (talc). However, in the paper dust removing apparatus 100 of the present embodiment, the nonwoven fabric sheet 108 can be brought into contact with the photosensitive drum 20 by its own weight, so that the pressing force at the time of contact can be significantly reduced. Therefore, paper dust can be removed satisfactorily and the same effect as the paper dust removing device 80 of the present embodiment can be achieved.
[0056]
  Further, according to the paper dust removing device 80 of the present embodiment shown in FIG. 2A, since the nonwoven fabric sheet 88 is in contact with the photosensitive drum 20 due to gravity acting on the nonwoven fabric sheet 88, the resin roller 86 is made of a nonwoven fabric sheet. It has been necessary to arrange 88 at a position higher than the position where it contacts the photosensitive drum 20. However, as described in the description of the arrangement example of the paper dust removing device 90 shown in FIG. 2B, if the non-woven sheet is thickened and has a waist, the non-woven sheet is not necessarily in contact with the photosensitive drum 20. It is not necessary to arrange in a higher position, and the position is not limited. A typical example is shown in FIG.
[0057]
  FIG. 4 shows a paper dust removing device 110 disposed below the photosensitive drum 20. The paper dust removing device 110 includes a support plate 115 as a base material, and a non-woven sheet 118 as a contact member that is thickened and has a waist and is further impregnated with an oil agent.
  Further, the paper dust removing device 110 embeds both ends of the nonwoven fabric sheet 118 in the support plate 115 and protrudes in a circular shape from the support plate 115.
[0058]
  In the paper dust removing device 110 configured in this way, the nonwoven fabric sheet 118 protruding from the support plate 115 is sufficiently thick so that the nonwoven fabric sheet 118 does not hang down due to its own weight, and the nonwoven fabric sheet 118 is removed from the lower side or the side. Can be contacted. Further, the paper dust removing device 110 has the support plate 115 as a base material on the back surface of the portion where the non-woven fabric sheet 118 contacts the photoconductor 20, so that the non-woven fabric sheet 118 is attached to the photosensitive drum 20 by the support plate 115. There is no strong pressing. Therefore, the pressing force of the nonwoven fabric sheet 118 against the photosensitive drum 20 can be remarkably reduced, paper dust can be removed well, and filming can be prevented from occurring. Also, the effect of removing paper dust can be increased by the cohesive force of the oil.
[0059]
  2B and 4, the paper dust removing devices 90 and 110 are not provided with a case 82 like the paper dust removing devices 80 and 100 shown in FIGS. 2A and 2C. Although displayed, of course, you may provide. In such a case, the scraped paper dust can be stored in the case 82 without being scattered around the photosensitive drum 20, so that the peripheral paper devices do not adversely affect the surrounding paper dust.
[0060]
  (Another embodiment using the paper dust removing device of the image forming apparatus of the present invention)
  Next, another embodiment using the paper dust removing device of the image forming apparatus of the present invention will be described with reference to FIG.
  In the above-described embodiment, the example in which the paper dust removing device of the image forming apparatus of the present invention is applied to the laser beam printer 1 that forms a black and white image has been described. However, the present invention is limited to the above-described embodiment. For example, as shown in FIG. 5, the paper dust removing device 80 may be brought into contact with the intermediate transfer belt 210 (intermediate transfer member) as a visible image carrier.
[0061]
  An image forming apparatus 200 shown in FIG. 5 is a color copying apparatus that forms a color image using four color toners. Although the feeder unit 10, the photosensitive drum 20, the charger 30, the laser scanner unit 40, and the fixing unit 70 are the same as the apparatus shown in FIG. 1, the developing device 50 is provided with a yellow toner. The difference is that four developing devices are provided: a developing device 50M having 5OY and magenta toner, a developing device 50C having cyan toner, and a developing device 50Bk having black toner. In the laser beam printer 1 of FIG. 1, the toner image is directly transferred from the photosensitive drum 20 to the paper P. However, the image forming apparatus 200 shown in FIG. This is different from the laser beam printer 1 of FIG. The intermediate transfer belt 210 is formed, for example, by forming conductive polyimide into a belt shape. When a voltage is applied while the intermediate transfer belt 210 is pressed against the toner on the photosensitive drum 20, the toner is transferred to the intermediate transfer belt 210 side by electrostatic force. Thereafter, when a voltage opposite to the toner and higher in voltage than the intermediate transfer belt is applied to the transfer roller 220, the toner is retransferred onto the paper P by electrostatic force. Thus, in this copying apparatus (image forming apparatus 200), it is not the photosensitive drum 20 but the intermediate transfer belt 210 that directly contacts the paper P. Therefore, in this case, in order to remove the paper dust adhering to the intermediate transfer belt 210, for example, a paper dust removing device 80, 90, 100, 110 as shown in FIG. 2 or FIG. 4 can be used. . Accordingly, the paper dust on the intermediate transfer belt 210 can be satisfactorily removed to prevent filming and to prevent image defects.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a schematic configuration of a usage form of a paper dust removing device of an image forming apparatus according to an embodiment.
FIG. 2 is a cross-sectional view (a) illustrating a configuration of a paper dust removing device of an image forming apparatus according to an embodiment, and cross-sectional views (b) and (c) illustrating another configuration of the paper dust removing device.
FIG. 3 is a cross-sectional view illustrating a configuration of a paper dust removing device of a conventional image forming apparatus.
FIG. 4 is a cross-sectional view illustrating a modification of the configuration of the paper dust removing device of the image forming apparatus according to the embodiment.
FIG. 5 is a cross-sectional view illustrating a schematic configuration of a modified example of a usage pattern of the paper dust removing device of the image forming apparatus according to the embodiment.
[Explanation of symbols]
  DESCRIPTION OF SYMBOLS 1 ... Laser beam printer, 20 ... Photosensitive drum, 30 ... Charger, 40 ... Laser scanner unit, 50 ... Developing apparatus, 60 ... Transfer roller, 70 ... Fixing unit, 80, 90, 100, 110, 120 ... Paper dust removal Device, 81, 101 ... Brush, 82, 102, 122 ... Case, 84, 104, 124 ... Roller shaft, 86 ... Resin roller, 106, 126 ... Elastic roller, 95, 115 ... Support plate, 88, 98, 108, 118, 128 ... Nonwoven fabric sheet, 200 ... Image forming apparatus (color copying apparatus), 210 ... Intermediate transfer belt, 220 ... Transfer roller, P ... Paper

Claims (4)

The electrostatic latent image formed on the photosensitive member is developed with a developer to form a visible image, and the visible image is transferred to a transfer medium such as paper, thereby forming an image on the transfer medium. In the apparatus, a paper dust removing device for removing paper dust from a visible image carrier that carries and conveys the visible image to a transfer position of the image,
In the vicinity of the moving path of the visible image carrier, a base material disposed at a predetermined interval from the visible image carrier,
A non-woven fabric, a woven fabric or a knitted fabric formed into a sheet shape, and a contact member supported by the substrate and partly in contact with the visible image carrier,
The contact point of the contact member with the visible image carrier is away from the base material ,
further, One end of the contact member is fixed to the substrate, and the other end contacts the visible image carrier, and is a paper dust removing device for an image forming apparatus. The base material rotates about an axis orthogonal to the moving direction of the visible image carrier, and the contact member contacts the visible image carrier by the rotation of the base material. Item 12. A paper dust removing device for an image forming apparatus according to Item 1. The electrostatic latent image formed on the photosensitive member is developed with a developer to form a visible image, and the visible image is transferred to a transfer medium such as paper, thereby forming an image on the transfer medium. In the apparatus, a paper dust removing device for removing paper dust from a visible image carrier that carries and conveys the visible image to a transfer position of the image,
In the vicinity of the moving path of the visible image carrier, a base material disposed at a predetermined interval from the visible image carrier,
A non-woven fabric, a woven fabric or a knitted fabric, comprising a contact member supported by the base material and partially contacting the visible image carrier,
The substrate is disposed at a position higher than the position where the previous term contact member in contact with the visible image bearing member, the contact member, the contact with the visible image bearing member by hanging by gravity from the substrate ,
The paper dust removing device for an image forming apparatus , wherein the contact member has one end fixed to the substrate and the other end is suspended by gravity, thereby contacting the visible image carrier . 4. The paper dust removing device for an image forming apparatus according to claim 3, wherein the contact member is formed in a sheet shape.

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