JP2000112311A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image forming device capable of surely removing paper powder even in the case of using an acidic paper as a transfer material. SOLUTION: A paper powder removing roller 82 is formed by winding a nonwoven sheet 85 impregnated with an oil agent on a sponge roller 84 pivotally supported by a shaft 83 and a paper powder removing device 80 is constituted by turnably arranging the roller 82 in a case 81. Then, the roller 82 is positioned so that the contact pressure of the roller 82 to a photoreceptor drum 20 becomes almost zero and is brought into contact with the drum 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper dust removing method for removing a paper dust on a photoconductor or an intermediate transfer member by bringing the toner image into contact with a photosensitive member or an intermediate transfer member which carries and transports a toner image to a transfer material. It belongs to the technical field of an image forming apparatus provided with a means.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus for forming an image by transferring a toner image on a photosensitive member or an intermediate transfer member to paper, a transfer residual toner on the photosensitive member or the intermediate transfer member is scraped with a blade or the like. There is a so-called cleaner-less development system in which a developer is collected and reused without taking it. In such a system, paper dust emitted from the paper is also collected by the developing device, and a printing defect occurs in which the paper dust is developed on a base or the like.

Therefore, a method has been proposed in which paper dust removing means is provided between the transfer means and the developing device.

[0004]

As this paper dust removing means, a rotary brush or a rotary nonwoven fabric has been proposed, but it has been very difficult to capture all the paper dust.
In particular, when acidic paper is used as a transfer material, there is a problem that even if a small amount of talc contained in the acidic paper is mixed into the developing device, fog is generated on a white background.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide an image forming apparatus capable of reliably removing paper dust even when acidic paper is used as a transfer material.

[0006]

According to a first aspect of the present invention, there is provided an image forming apparatus, comprising: developing an electrostatic latent image formed on a photoreceptor with a developer to form a visible image; An image forming apparatus for forming an image by forming and transferring the visible image to a transfer medium, comprising: a visible image carrier for carrying the visible image at the transfer position; A paper dust removing means for removing paper dust on the visible image carrier, comprising a contact member for contacting the body, wherein the contact member of the paper dust removing means is made of a fiber impregnated with an oil agent. It is characterized by comprising a member.

According to the image forming apparatus of the first aspect,
When the visible image carrier carries and transports a visible image composed of a developer to a transfer position, the visible image is transferred to a transfer medium,
When paper is used as the transfer medium, paper powder adheres to the visible image carrier in this transfer step. However, the contact member of the paper dust removing paper means is in contact with the visible image carrier, and the wiping or sweeping force of the fiber member constituting the contact member is impregnated with the fiber member. The paper powder is surely removed by the cohesive force of the oil agent.

According to a second aspect of the present invention, in order to solve the above-mentioned problem, in the image forming apparatus according to the first aspect, the paper dust removing means includes a fiber around a rotatable support member. It is characterized by having a member made of.

According to the image forming apparatus of the present invention,
Even when the support member is rotated by the driving force, or when the support member is driven to rotate with respect to the visible image carrier, the fiber member provided around the support member rotates with the rotation of the support member. Therefore, the contact portions of the fiber member with the visible image carrier move one after another. Therefore, the removed paper dust is not accumulated in the contact portion, thereby preventing the visible image carrier from being damaged.

According to a third aspect of the present invention, there is provided an image forming apparatus according to the first or second aspect, wherein the fiber member of the paper dust removing means comprises a fiber. It is characterized by being made of any one of a brush, a nonwoven fabric, a woven fabric, and a knit.

According to the image forming apparatus of the third aspect,
Since the paper powder removing means makes any one of a fiber brush impregnated with the oil agent, a nonwoven fabric, a woven fabric, and a knitted fabric contact the visible image carrier, a soft fiber brush, a nonwoven fabric, a woven fabric, Alternatively, while preventing the surface of the visible image carrier from being damaged by the knitted fabric, the paper powder was removed by these wiping forces or sweeping forces, and the cohesive force of the oil agent impregnated in these materials could not remove them alone. Also removes paper dust.

According to a fourth aspect of the present invention, there is provided an image forming apparatus according to the second or third aspect, wherein the paper dust removing means comprises: One end is an attachment end to the support member,
It is a sheet-like member having the other end as a free end.

According to the image forming apparatus of the fourth aspect,
One end is attached to the support member, and the free end of the sheet-like fibrous member impregnated with the oil agent contacts the visible image carrier, so that the surface of the visible image carrier is pressed with a strong force. To prevent filming phenomenon caused by oil. Further, the visible image carrier is not damaged by the removed paper dust.

According to a fifth aspect of the present invention, in order to solve the above-mentioned problems, in the image forming apparatus according to the fourth aspect, the fiber member of the paper dust removing means is made of non-woven fabric, woven fabric, or It is characterized by being composed of any one of the knits.

According to the image forming apparatus of the fifth aspect,
One end is attached to the support member, and the free end of the sheet-like nonwoven fabric, woven fabric, or knit impregnated with the oil agent comes into contact with the visible image carrier, so that the surface of the visible image carrier is strongly pressed. To prevent the filming phenomenon due to the oil agent. In addition, while preventing the surface of the visible image carrier from being damaged by soft non-woven fabric, woven fabric, or knitted fabric,
Paper dust is removed by these wiping or sweeping forces, and furthermore, by the cohesive force of the oil agent impregnated in them, paper dust that cannot be removed by these alone is also removed.
Due to the extremely small pressing force, the visible image carrier is not damaged by the removed paper dust.

According to a sixth aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects, in order to solve the above-mentioned problem, the visible portion of the fiber member is provided. The contact pressure on the image carrier is set to be substantially zero.

According to the image forming apparatus of the sixth aspect,
Since the fiber member is in contact with the visible image carrier at substantially zero contact pressure, it reliably prevents filming of the oil agent on the surface of the visible image carrier, and the removed paper powder The surface of the visible image carrier is not damaged.

According to a seventh aspect of the present invention, there is provided an image forming apparatus according to any one of the first to sixth aspects, wherein the oil agent is mineral oil, synthetic oil, It is characterized by containing at least one or more of oil, silicone oil, and surfactant.

According to the image forming apparatus of the present invention,
The fibrous member is impregnated with an oil agent containing at least one of mineral oil, synthetic oil, silicone oil, and surfactant, and is brought into contact with the visible image carrier. Remove the powder.

According to an eighth aspect of the present invention, there is provided an image forming apparatus according to any one of the first to seventh aspects, wherein the transfer residual developer is developed by the developing device. And a cleaner-less developing method in which the developer is used again for development.

According to the image forming apparatus of the present invention,
The untransferred developer remaining on the visible image carrier after the transfer step is collected by a developing device and subjected to development again, but the paper dust on the visible image carrier is removed by the above-described paper dust removing means. Therefore, paper powder is not mixed when the transfer agent developer is collected in the developing device. Therefore, image defects such as fogging do not occur.

According to a ninth aspect of the present invention, in the image forming apparatus according to any one of the first to eighth aspects, the visible image carrier may be It is characterized in that the photoreceptor doubles.

According to the image forming apparatus of the ninth aspect,
The visible image formed by development is carried on the photoconductor,
It is carried and conveyed to a transfer position and is transferred to a transfer medium. Accordingly, paper dust adheres to the photoreceptor, but the paper dust is surely removed by the paper dust removing means, so that an image defect does not particularly occur when a visible image is formed on the photoreceptor.

According to a tenth aspect of the present invention, in the image forming apparatus according to any one of the first to eighth aspects, the visible image carrier is provided with It is characterized by comprising an intermediate transfer member provided endlessly movably facing the photosensitive member.

According to the image forming apparatus of the present invention, the visible image formed by the development is carried on the photosensitive member, and is transferred to the intermediate transfer member which is provided endlessly to face the photosensitive member. Transcribed. Then, the image is retransferred from the intermediate transfer member to a transfer medium. Therefore, paper dust adheres to the intermediate transfer member, but the paper dust is surely removed by the paper dust removing means, so that the transfer of the paper dust from the intermediate transfer member to the photoconductor or the intermediate transfer Prevents transfer of paper powder from the body to the transfer medium, and does not cause image defects.

[0026]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a schematic configuration of a laser beam printer 1 as an embodiment of the image forming apparatus of the present invention. In FIG. 1, a laser beam printer 1 is
A feeder unit 10 for feeding paper P as a transfer medium is provided at the bottom of the main body case 2. The feeder unit 10 includes a paper pressing plate 11, a compression spring 12, and a paper feed roller 13.
, The uppermost sheet P is supplied at a predetermined timing.

A pair of registration rollers 14 and 1 are located downstream of the paper feed roller 13 in the transport direction indicated by arrow A.
5 is rotatably supported, and conveys the sheet P to a transfer position formed by the photosensitive drum 20 and the transfer roller 60, which will be described later, at a predetermined timing.

The photosensitive drum 20 as a photosensitive member and a visible image carrier is made of a positively chargeable material, for example, an organic photosensitive member mainly containing a positively chargeable polycarbonate. Specifically, as shown in FIG. 2, the photosensitive drum 20 is, for example,
A hollow drum having a cylindrical aluminum sleeve 21 as a main body and a photoconductive layer 22 of a predetermined thickness (for example, about 20 μm) in which a photoconductive resin is dispersed in polycarbonate is formed on the outer periphery thereof. Composed, cylindrical sleeve 2
1 is rotatably supported by the main body case 2 in a state of being grounded. Further, the photosensitive drum 20 is driven to rotate in the direction of arrow B by a driving unit (not shown). The charger 30 is, for example, a scorotron-type 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) for generating a laser beam L for forming an electrostatic latent image on the photosensitive drum 20, and a polygon mirror (pentahedral mirror) 41 that is driven to rotate. , A pair of lenses 42 and 4
3 and a pair of reflecting mirrors 44 and 45.

In the developing device 50, a toner accommodating chamber 52 is formed in a case 51. In the toner accommodating chamber 52, an agitator 53 and a toner as a positively chargeable non-magnetic one-component developer having an electrically insulating property are provided. 54 are accommodated. A developing chamber 55 for performing development is formed adjacent to the toner storage chamber 52,
The supply roller 56 and the developing roller 57 are rotatably supported. The toner 54 on the developing roller 57 is regulated to a predetermined layer thickness by a thin plate-like elastic layer thickness regulating blade 58 and is used for development.

The transfer roller 60 is rotatably supported, and
It is made of a conductive foamed elastic body made of silicon rubber or urethane rubber. Depending on the applied voltage,
The toner image on the photosensitive drum 20 is reliably transferred to the sheet P.

The fixing unit 70 is provided downstream of the photosensitive drum 20 in the transport direction of the sheet P indicated by the arrow A,
A heating roller 71 and a pressing roller 72 are provided. The toner image transferred onto the paper P is pressed while being heated, and
Is established.

A pair of transport rollers 73 and a discharge roller 74 for transporting the paper are provided on the downstream side of the fixing unit 70 in the transport direction, and a discharge tray 75 is provided on the downstream side of the discharge roller 74. Have been.

In the laser beam printer 1 of the present embodiment as described above, the surface of the photosensitive drum 20 is
When the laser beam L modulated according to image information is emitted from the laser scanner unit 40, an electrostatic latent image is formed on the surface of the photosensitive drum 20.
This electrostatic latent image is visualized by the toner 54 by the developing device 50, and the visible image formed on the photosensitive drum 20 is transported by the photosensitive drum 20 to a transfer position. 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 by the transfer roller 60. Next, the paper P is transported to the fixing unit 70 and the heating roller 71 of the fixing unit 70
The visible image on the paper P is pressed and heated, and is fixed on the paper P. Then, the sheet P is transferred to a pair of transport rollers 73 and a discharge roller 74.
Is discharged to the discharge tray 75 above the laser beam printer 1, and the image forming operation is completed. On the other hand, the toner remaining on the photosensitive drum 20 after the transfer is collected by the developing device 50 and is again used for development. As described above, the laser beam printer 1 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 size of the apparatus can be reduced, and the toner can be effectively used.

However, conventionally, when the cleaner-less developing method is adopted, 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, and image defects are caused. May occur.

Here, the relationship between paper dust and image defects will be described in detail. In addition to pulp fiber (cellulose extracted from hardwood and softwood), which is the main raw material for paper, fillers that make paper opaque and white, internal sizing agents to prevent ink bleeding, and sizing agents And an internal-size fixing agent that causes pulp fibers to be adsorbed. The above-mentioned acidic paper mainly uses talc or clay as a filler, a rosin sizing agent as an internal sizing agent, and a sulfate band (aluminum sulfate) as an internal sizing agent.

Among them, substances which 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 caught between the layer thickness regulating blade and the developing roller, and may damage the layer thickness regulating blade and the developing roller. Further, the pulp fiber passes through the layer thickness regulating blade together with the toner wrapped around the pulp fiber to form a paper P.
If it adheres to the top and is discharged as it is through the fixing process, it will be recognized by the naked eye as conspicuous dust particularly when it adheres to a solid white portion. On the other hand, talc is a very strongly negatively charged substance, and in a process using a positively charged toner, if it is mixed in a developing device, the amount of charge of the toner is reduced to cause printing fog. Further, in a process using a negatively charged toner, similarly, it may cause print fogging, or even if not fog, the charge amount of the toner becomes excessively high, causing a decrease in image density. is there.

In order to remove such paper dust, a device in which a paper dust removing means using a rotary brush or a nonwoven fabric is brought into contact with a photosensitive drum has been proposed. Simply contacting the photosensitive drum with the photosensitive drum could not sufficiently capture the paper dust, and could not solve the above-mentioned problem. In particular, when acidic paper is used as the paper, even if a small amount of talc contained in the acidic paper is mixed in the developing device, fogging occurs, and thus such a problem occurs remarkably.

However, if the paper dust removing means is strongly pressed against the photosensitive drum in order to enhance the paper dust removing ability of the paper dust removing means, the captured hard pulp fibers may damage the surface of the photosensitive drum. There was a problem. 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 means or between the photosensitive drum surface and the pulp fibers accumulated in the paper dust removing means. Then, the filler is thinly attached to the surface of the photosensitive drum, and a phenomenon called filming occurs. When filming occurs, the charged potential of the photosensitive drum surface before and after the exposure changes, making it impossible to form an appropriate image or causing poor transfer of the toner due to poor toner releasability. was there.

Therefore, in the present embodiment, in order to solve the above-mentioned problems, a paper dust removing means is constituted by impregnating an oil agent into a non-woven fabric, a woven fabric, a knitted fabric or the like, or an insulating brush fiber. As a result, paper dust is reliably removed. Hereinafter, the configuration of the paper dust removing unit in the present embodiment will be described in detail.

As shown in FIG. 1, the paper dust removing device 80 of this embodiment includes a paper dust removing roller 82 in a case 81. As shown in FIG. 3, the paper dust removing roller 82 has an elastic roller 84 such as a sponge as a support member formed on a shaft 83 made of metal such as aluminum. A nonwoven fabric sheet 85 as a contact member impregnated with an oil agent is wound.

In this embodiment, the nonwoven fabric sheet 85
Used what was integrated by confounding the constituent fibers. This is because it is preferable to use a component fiber having a high degree of freedom in capturing fine paper powder between the fibers.
As a 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, a recycled fiber such as cupra or rayon, a natural fiber such as wire, hemp, wool, or a fiber member such as a cotton blend is used.

As the oil agent to be impregnated into the nonwoven fabric sheet 85, a material containing at least one of mineral oil, synthetic oil, silicone oil and surfactant was used. As mineral oils, paraffinic hydrocarbons,
Naphthenic hydrocarbons, aromatic hydrocarbons and the like are used.
As the synthetic oil, an alkylbenzene oil, a polyolefin oil, a polyglycol oil, or the like is used. Further, as the silicone oil, chain dimethylpolysiloxane, cyclic dimethylpolysiloxane, methylhydrogenpolysiloxane, various modified silicones and the like are used. As the surfactant, a quaternary ammonium salt type or the like is preferable as a cationic type, and a polyethylene glycol type or a polyhydric alcohol type or the like is preferable as a nonionic type. In the present embodiment, such an oil agent is carried at a ratio of 1 to 20% based on the weight of the nonwoven fabric sheet 85.

In this embodiment, the paper dust removing roller 82 is positioned so that the pressing force against the photosensitive drum 20 becomes substantially zero, and the transfer amount of the oil agent to the photosensitive drum 20 is minimized. I have. Accordingly, the oiling agent does not adhere to the photosensitive drum 20 in a large amount, and filming by the oiling agent can be prevented. Further, filming due to soft talc as described above can be prevented.

Even when the pressing force of the paper dust removing roller 82 against the photosensitive drum 20 is substantially zero, the nonwoven fabric sheet 85 is impregnated with the above-described oil agent, so that the pulp fibers or the pulp fibers are surely formed by the cohesive force of the oil agent. Paper powder such as talc can be removed. In particular, even when an acidic paper is used as the paper P, the components of the paper (particularly, talc) can be reliably removed, and image defects such as fog can be reliably prevented.

Therefore, according to this embodiment, no filming of the photosensitive drum 20 occurs, no mixing of pulp fibers or talc into the developing device 50, and no transfer of pulp fibers to the paper P occurs. Image defects such as fog or paper stains can be reliably prevented.

The paper dust removing roller 82 of the present embodiment
Is configured to rotate in accordance with the rotation of the photosensitive drum 20 in the direction of the arrow, and a storage space for the case 81 is formed below the paper dust removal roller 82. It does not fall into the storage space and accumulate in the contact portion between the paper dust removing roller 82 and the photosensitive drum 20.

Therefore, the surface of the photosensitive drum 20 is not damaged by the hard pulp fiber, and filming by soft talc can be reliably prevented.

(Another embodiment of paper dust removing means) Next, another embodiment of the paper dust removing means of the present invention will be described with reference to FIGS.

In the embodiment described above, an example is described in which the paper dust removing means of the present invention uses a non-woven sheet wound on an elastic roller, but the present invention is not limited to this. For example, a configuration as shown in FIG. Paper dust removing device 90 shown in FIG.
A paper dust removing roller 93 is formed by attaching one end of a strip-shaped nonwoven fabric sheet 92 as a contact member to a rigid roller 91 as a support member, and using the other end as a free end so as to overlap each other. A powder removing roller 93 is rotatably provided in a case 94, and is rotated in the same direction as the photosensitive drum 20 by a driving unit (not shown). Therefore, at the contact portion with the photosensitive drum 20, the nonwoven fabric sheet 92 moves in the counter direction. Further, inside the case 94, a scraping member 95 that comes into contact with the nonwoven fabric sheet 92 and scrapes the paper dust on the nonwoven fabric sheet 92 is attached. Also in the paper dust removing roller 93, the nonwoven fabric sheet 92 is impregnated with the oil agent as described above. By using such a paper dust removing device 90, the pressing force of the nonwoven fabric sheet 92 against the photosensitive drum 20 can be significantly reduced, and the paper on the photosensitive drum 20 can be reduced by the cohesive force of the oil agent and the wiping force of the nonwoven fabric sheet. Powder can be reliably removed.

Further, a configuration as shown in FIG. 5 can be adopted. The paper dust removing device 100 shown in FIG. 5 uses a paper dust removing roller 103 in which an insulating brush 102 is attached as a contact member on a rigid roller 101 as a supporting member. The paper dust removing roller 103 is rotatably provided in the case 104, and is rotated in the same direction as the photosensitive drum 20 by a driving unit (not shown). Also, the case 104
Inside, the scraping member 1 that contacts the brush 102
05 is provided. And even in this case, the brush 1
02 is impregnated with the oil agent described above. By using such a paper dust removing device 100, the photosensitive drum 2
The pressing force of the brush 102 with respect to zero can be significantly reduced, and the paper dust on the photosensitive drum 20 can be reliably removed by the cohesive force of the oil agent and the wiping force of the brush.

Further, the configuration may be as shown in FIG.
In the paper dust removing device 110 shown in FIG. 6, the brush 102 is attached to the support member 106 and is fixedly provided in the case 104. Also in this case, the brush 102 is impregnated with the above-described oil agent. By using such a paper dust removing device 110, the configuration can be simplified, the pressing force of the brush 102 against the photosensitive drum 20 can be significantly reduced, and the cohesive force of the oil agent and the brush Paper dust on the photosensitive drum 20 can be reliably removed by the wiping force. However, in such a configuration, paper dust easily accumulates at the contact portion between the brush 102 and the photosensitive drum 20, but by adjusting the contact angle of the brush 102 with the photosensitive drum 20, there is no practical problem. The paper powder removed at the time can be dropped into the case 104.

Further, the configuration may be as shown in FIG.
The paper dust removing device 120 shown in FIG.
Is supported by a support member 122, and the support member 122 is attached to the case 51 of the developing device 50. Also in this case, the nonwoven fabric sheet 121 is impregnated with the above-described oil agent. In such a configuration, the removed paper dust tends to accumulate at the contact portion between the nonwoven fabric sheet 121 and the photosensitive drum 20, but the pressing force of the nonwoven fabric sheet 121 against the photosensitive drum 20 is substantially zero. By doing so, the accumulated amount can be suppressed to a level that does not cause a practical problem. The paper dust removing device 120 is formed integrally with the case 51 of the developing device 50. Since the developing device 50 is a cartridge type developing device detachable from the laser beam printer 1, the developing device 5
By exchanging 0, a new paper dust removing device 120 can be exchanged. Therefore, paper dust does not accumulate between the nonwoven fabric sheet 121 and the photosensitive drum 20 for a long period of time.
When such a paper dust removing device 120 is used, paper dust on the photosensitive drum 20 can be reliably removed by the cohesive force of the oil agent and the wiping force of the nonwoven fabric sheet.

Further, in each of the above-described examples, the paper dust removing means is brought into contact with the photosensitive drum as the visible image carrier. However, the present invention is not limited to this, and as shown in FIG. The paper dust removing means may be brought into contact with an intermediate transfer belt (intermediate transfer member) as a visible image carrier.

The image forming apparatus 200 shown in FIG. 8 is a color copying apparatus for forming a color image using four color toners. Feeder unit 10, photosensitive drum 20, charger 30, laser scanner unit 40, fixing unit 70
1 is common to the apparatus shown in FIG. 1, but as a developing device, a developing device 50 having a yellow toner is used.
The difference is that a developing device 50M having a Y and magenta toner, a developing device 50C having a cyan toner, and a developing device 50Bk having a black toner are provided. Further, in the laser beam printer 1 shown in FIG. 1, the toner image is directly transferred from the photosensitive drum 20 to the paper P. However, the apparatus shown in FIG. It is different from the beam printer 1. This intermediate transfer belt 201 is
For example, a chargeable polyimide is formed in a belt shape. When a voltage is applied while the intermediate transfer belt 201 is pressed against the toner on the photosensitive drum 20, the toner is transferred to the intermediate transfer belt 201 by electrostatic force. Thereafter, when a voltage having a polarity opposite to that of the toner and higher than that of the intermediate transfer belt is applied to the transfer roller 202, the toner is retransferred to the paper P by electrostatic force. As described above, in this copying apparatus, the intermediate transfer belt 201 is not in direct contact with the sheet P, but the photosensitive drum 20. Therefore, in this case, for example, the nonwoven fabric sheet 92 of the paper dust removing device 90 shown in FIG. This makes it possible to reliably remove the paper dust on the intermediate transfer belt 201 and prevent image defects.

[0057]

According to the image forming apparatus of the present invention, the contact member of the paper dust removing means is constituted by the fiber member in which the fiber is impregnated with the oil agent. Paper powder can be reliably removed by the take-up force and the cohesive force of the oil agent. In particular, when acid paper is used, talc can be reliably removed, and image defects such as fog can be reliably prevented.

According to the image forming apparatus of the second aspect,
Since the paper dust removing means including the fiber member is provided around the rotatable support member, the contact portions of the fiber member with the visible image carrier move one after another, and the contact portion of the removed paper dust is moved. Can be prevented from accumulating. As a result, damage to the visible image carrier can be prevented.

According to the image forming apparatus of the third aspect,
Since the fiber member of the paper dust removing means is composed of any one of a fiber brush, a nonwoven fabric, a woven fabric, and a knitted fabric, the wiping force or the sweeping force of these components is prevented while preventing the surface of the visible image carrier from being damaged. Paper dust can be removed by the removing force. Furthermore, by the cohesive force of the oil agent impregnated in these,
Even paper dust that could not be removed by these alone can be removed.

According to the image forming apparatus of the fourth aspect,
Since the paper dust removing means is provided with a sheet-like fiber member having one end attached to the support member and the other end as a free end, the surface of the visible image carrier is not pressed with a strong force, and Can prevent the filming phenomenon. Further, it is possible to prevent the visible image carrier from being damaged by the removed paper dust.

According to the image forming apparatus of the fifth aspect,
Since the fiber member of the paper dust removing means of claim 4 is made of any one of a nonwoven fabric, a woven fabric, and a knitted fabric, the filming phenomenon caused by the oil agent is prevented, and the paper dust is reliably removed. Due to the extremely small pressing force, it is possible to reliably prevent the visible image carrier from being damaged by the removed paper dust.

According to the image forming apparatus of the sixth aspect,
Since the contact pressure of the fiber member with respect to the visible image carrier is set to be substantially zero, filming of the oil agent on the surface of the visible image carrier can be reliably prevented, and the removed paper dust Damage to the surface of the visible image carrier can be reliably prevented.

According to the image forming apparatus of the seventh aspect,
Since an oil agent containing at least one of mineral oil, synthetic oil, silicone oil, and surfactant is used, paper powder can be reliably removed with good cohesion.

According to the image forming apparatus of the present invention,
An image forming apparatus using a cleaner-less developing method in which the transfer residual developer is collected by the developing device and used again for development is provided with the above-described paper dust removing means, so that the transfer agent developer is transferred to the developing device. An image forming apparatus having a simple configuration that can reliably prevent paper dust from being mixed at the time of collection and that does not cause image defects such as fog can be provided.

According to the image forming apparatus of the ninth aspect,
Since the image forming apparatus in which the photoreceptor is a visible image carrier is provided with the above-described paper dust removing means, it is possible to reliably prevent an image defect particularly when a visible image is formed on the photoreceptor.

According to a tenth aspect of the present invention, there is provided an image forming apparatus in which the intermediate transfer member provided to be endlessly movable facing the photosensitive member is a visible image carrier. Since the removing means is provided, the transfer of paper dust from the intermediate transfer member to the photoreceptor or the transfer of paper powder from the intermediate transfer member to the transfer medium can be reliably prevented, and an image forming apparatus that does not cause image defects Can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a configuration of a photosensitive drum in the image forming apparatus of FIG.

FIG. 3 is a sectional view illustrating a configuration of a paper dust removing device in the image forming apparatus of FIG. 1;

FIG. 4 is a sectional view showing a modified example of the paper dust removing device of the present invention (part 1).

FIG. 5 is a sectional view showing a modification of the paper dust removing device of the present invention (part 2).

FIG. 6 is a sectional view showing a modified example of the paper dust removing device of the present invention (part 3).

FIG. 7 is a sectional view showing a modification of the paper dust removing device of the present invention (part 4).

FIG. 8 is a cross-sectional view showing a modification of the usage mode of the paper dust removing device of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laser beam printer 20 photosensitive drum 80, 90, 100, 110, 120 paper dust removing device 82, 93, 103 paper dust removing roller 85, 92, 121 nonwoven fabric sheet 102 brush 200 image forming device (color copying device) 201 intermediate transfer belt

Claims (10)

[Claims] An image forming apparatus that develops an electrostatic latent image formed on a photoreceptor with a developer to form a visible image, and transfers the visible image to a transfer medium to form an image. A visible image carrier that carries and conveys the visible image to the transfer position; and a contact member that contacts the visible image carrier to remove paper dust on the visible image carrier. An image forming apparatus comprising: a paper dust removing unit; and a contact member of the paper dust removing unit is a fiber member in which a fiber is impregnated with an oil agent. 2. The image forming apparatus according to claim 1, wherein the paper dust removing unit includes the fiber member around a rotatable support member. 3. The fiber member of the paper dust removing means,
3. A fiber brush, a nonwoven fabric, a woven fabric, or a knitted fabric.
An image forming apparatus according to claim 1. 4. The paper dust removing means according to claim 2, wherein the fiber member is a sheet-like member having one end serving as an attachment end to the support member and the other end as a free end. The image forming apparatus according to claim 3. 5. The fiber member of the paper dust removing means,
The image forming apparatus according to claim 4, wherein the image forming apparatus is made of any one of a nonwoven fabric, a woven fabric, and a knit. 6. The apparatus according to claim 1, wherein a contact pressure of the fiber member with respect to the visible image carrier is set to be substantially zero. Image forming device. 7. The method according to claim 1, wherein the oil agent contains at least one of a mineral oil, a synthetic oil, a silicone oil, and a surfactant. Image forming device. 8. The image forming apparatus according to claim 1, wherein a cleaner-less developing system is used in which the transfer residual developer is collected by a developing device and is used again for development. apparatus. 9. The image forming apparatus according to claim 1, wherein the photoconductor also serves as the visible image carrier. 10. The image forming apparatus according to claim 1, wherein the visible image carrier is formed of an intermediate transfer member that is provided so as to be movable endlessly so as to face the photoconductor. The image forming apparatus as described in the above.