JP2000112312A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image forming device capable of surely removing paper powder whatever kind the paper powder is. SOLUTION: A 1st paper powder removing device 80 where a brush 83 is supported by supporting member 82 attached inside a case 81 and which mainly removes pulp fiber out of the paper powder, is provided on the downstream side in the rotating direction of a photoreceptor drum 20 from a transfer position where a transfer roller and the drum 20 are opposed to each other and the brush 83 is brought into contact with the drum 20. Further, a 2nd paper powder removing device 90 where nonwovon fabric 92 backed with a sponge 93 is supported by a supporting member 91 attached to the case 51 of a developing device 50 and which mainly removes talc out of the paper powder is provided on the downstream side in the rotating direction of the drum 20 rather from the contact position and the nonwoven fabric 92 is brought into contact with the drum 20 so that the contact pressure to the drum 20 becomes almost zero.

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 a paper dust removing means provided with a rotary or fixed brush or nonwoven fabric is provided between the transfer means and the developing device.

[0004]

However, it is very difficult to remove all the paper dust by the conventional paper dust removing means.

For example, when a brush is used, relatively large pulp fibers contained in paper powder can be removed satisfactorily, but there is a problem that filler such as talc is relatively difficult to remove.

[0006] On the other hand, when a nonwoven fabric is used, pulp fibers and talc can be removed well, but the removed paper powder is retained.
For example, there is a problem that talc accumulated at a contact portion between the surface of the photosensitive drum and the nonwoven fabric causes filming of talc on the surface of the photosensitive drum.

[0007] In order to prevent such filming, it is conceivable that a nonwoven fabric made of a soft material is brought into contact with an extremely low contact pressure. Is trapped and accumulated in the nonwoven fabric, so that the effect of lowering the contact pressure is lost, and there is a problem that filming by talc occurs and the surface of the photosensitive drum is damaged by pulp fibers.

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 any type of paper dust.

[0009]

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; Forming, transferring the visible image to a transfer position by a visible image carrier,
An image forming apparatus for forming an image by transferring the visible image from the visible image carrier to a transfer medium, wherein the image forming apparatus is located downstream of the transfer position in the rotation direction of the visible image carrier. A first paper dust removing unit that comes into contact with the visual image carrier and mainly removes fiber components of the paper dust, and the visible image is located at a position where the first paper dust removing unit is in contact with the visible image carrier. A second paper dust removing means is provided which is in contact with the visible image carrier on the downstream side in the rotation direction of the carrier and mainly removes a filler component of the paper dust.

According to the image forming apparatus of the first aspect,
The visible image carried on the visible image carrier is transferred to the transfer medium at the transfer position. At this time, the paper dust of the transfer medium adheres to the visible image carrier, but is more visible than the transfer position. Since the first paper dust removing means is in contact with the visible image carrier on the downstream side in the rotation direction of the image carrier, mainly the fiber component of the paper dust is removed by the first paper dust removing means. . Further, the second paper dust removing unit contacts the visible image carrier downstream of the contact position of the first paper dust removing unit with the visible image carrier in the rotation direction of the visible image carrier. are doing. Therefore, the contact position of the second paper dust removing unit with the visible image carrier is
The paper dust containing no fiber component is conveyed, and the fiber component of the paper dust is not accumulated at the contact position. As a result, without causing filming of the filler component of the paper dust by the accumulated fiber component, the second paper dust removing unit can
The filler component of the paper powder is reliably removed. As described above, according to the present invention, both the fiber component and the filler component of the paper powder are reliably removed.

According to a second aspect of the present invention, in order to solve the above problem, an electrostatic latent image formed on a photoreceptor is
Developing with a developer to form a visible image, transferring the visible image to a transfer position by a visible image carrier, and transferring the visible image from the visible image carrier to a transfer medium An image forming apparatus for forming a first paper dust removing means including a brush member that comes into contact with the visible image carrier at a position downstream of the transfer position in the rotational direction of the visible image carrier; It is formed of a nonwoven fabric, a woven fabric, or a knitted fabric that comes into contact with the visible image carrier at a position downstream of the contact position of the first paper dust removing unit with the visible image carrier in the rotation direction of the visible image carrier. A second paper dust removing means including a fiber member.

According to the image forming apparatus of the second aspect,
The visible image carried on the visible image carrier is transferred to the transfer medium at the transfer position. At this time, the paper dust of the transfer medium adheres to the visible image carrier, but is more visible than the transfer position. Since the first paper dust removing means including the brush member is in contact with the visible image carrier on the downstream side in the rotation direction of the image carrier, mainly the fiber component of the paper dust mainly contains the first paper dust removing means. Of the brush member. In addition, a second portion including a fibrous member made of a nonwoven fabric, a woven fabric, or a knitted material is provided downstream of the contact position of the first paper dust removing unit with the visible image carrier in the rotation direction of the visible image carrier. The paper dust removing means is in contact with the visible image carrier. Therefore, the paper dust containing no fiber component is conveyed to the contact position of the second paper dust removal unit with the visible image carrier, and the fiber component of the paper dust is not accumulated at the contact position. . As a result, the filler component of the paper dust is surely removed by the fiber member of the second paper dust removing means without causing filming of the filler component of the paper dust by the accumulated fiber component. As described above, according to the present invention, both the fiber component and the filler component of the paper powder are reliably removed.

According to a third aspect of the present invention, in order to solve the above-mentioned problem, in the image forming apparatus according to the second aspect, the first paper dust removing means includes a roller-shaped brush member. It is characterized by the following.

According to the image forming apparatus of the third aspect,
Of the paper dust adhering to the visible image carrier immediately after the transfer, the fiber component is removed by the roller-shaped brush member included in the first paper dust removing unit. Therefore, the contact points of the brush member with the visible image carrier are successively changed with the rotation of the roller-shaped brush member, so that the paper dust scraping force of the brush member is further improved and the second paper dust is removed. There is no accumulation of the fiber component of the paper dust at the contact position between the removing means and the visible image carrier.

According to a fourth aspect of the present invention, in order to solve the above-mentioned problem, in the image forming apparatus according to the second aspect, the first paper dust removing means includes a paper dust storage having an opening. And a brush member fixedly attached to the paper dust storage member, wherein the opening of the paper dust storage member stores paper dust that is removed by the brush member and drops by gravity. It is characterized in that it is formed at a position and size for guiding inside the member.

According to the image forming apparatus of the fourth aspect,
The paper dust removed from the visible image carrier by the brush member fixedly attached to the paper dust accommodating member of the first paper dust removing means falls due to gravity, and from the opening of the paper dust accommodating member. It is guided and stored inside the paper dust storage member. Therefore, no paper dust is accumulated in the contact portion between the brush member and the visible image carrier, and the inside of the image forming apparatus is not stained with the paper dust.

According to a fifth aspect of the present invention, there is provided an image forming apparatus according to any one of the first to fourth aspects, wherein the developing device is an image forming apparatus. And the second paper dust removing means is attached to the detachable developing device.

According to the image forming apparatus of the fifth aspect,
If the image deteriorates due to a decrease in the remaining amount of the developer or the like, a good image can be formed by removing the developing device from the image forming device and installing a new developing device. When the developing device is replaced, the second paper dust removing means attached to the developing device is also replaced at the same time. Therefore, even if the paper dust accumulates at the contact portion between the second paper dust removing means for mainly removing the filler component of the paper dust and the visible image carrier, the accumulated paper dust may damage or damage the visible image carrier. Filming can be prevented from occurring.

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 image forming apparatus according to any one of the first to fifth aspects, further comprising: It is characterized by using a cleaner-less developing system in which the toner is collected by an apparatus and then subjected to development again.

According to the image forming apparatus of the sixth aspect,
Transfer residual developer remaining on the visible image carrier after the transfer step is
The cleaner-less development method in which the toner is collected by the developing device and is subjected to the development again is used. However, as described above, the paper powder on the visible image carrier reliably removes both the fiber component and the filler component. Therefore, these paper dusts do not enter the developing device, and image defects caused by these can be reliably prevented.

[0021]

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 composed of 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 an electrically insulating positively chargeable non-magnetic one-component developer 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,
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 on the downstream side 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 to the lower surface of the sheet P is pressed while being heated and is fixed on the sheet P.

A pair of paper transport rollers 73 and a paper discharge roller 74 for paper transport are provided on the downstream side in the transport direction of the fixing unit 70, respectively, and a paper discharge tray 75 is provided on the downstream side of the paper 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. After the transfer, the photosensitive drum 2
The toner remaining on the toner image 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. Next, the paper P is conveyed to the fixing unit 70, 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 pressed and heated to be fixed on the paper P. You. Then, the sheet P is discharged out of a sheet discharge tray 75 above the laser beam printer 1 by a pair of conveying rollers 73 and a sheet discharge roller 74,
The image forming operation ends.

As described above, in the laser beam printer 1 according to the present embodiment, since the surface of the photosensitive drum 20 comes into direct contact with the paper P, paper dust easily adheres to the surface of the photosensitive drum 20. Is collected by the developing device 50 together with the toner remaining on the photosensitive drum 20, which may cause an image defect.

Here, the paper powder 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 these, pulp fibers and filler talc are substances that particularly adversely affect the electrophotographic process. 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. In addition, talc is a substance having a considerably strong negative charge. In a process using a positively charged toner, when it is mixed in a developing device, the charge amount of the toner is reduced, which causes print 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, there has conventionally been proposed an apparatus in which a rotary or fixed brush is brought into contact with the photosensitive drum, or a pad made of nonwoven fabric or the like is brought into contact with the photosensitive drum. However, none of these methods could reliably prevent printing defects due to both pulp fibers and talc.

That is, when a rotary or fixed brush is used, relatively large pulp fibers contained in paper powder can be removed, but filler such as talc is sufficiently removed. I couldn't do that. On the other hand, when a nonwoven fabric is used, both the pulp fiber and talc can be removed.However, since the removed paper dust is retained, the talc accumulated at the contact portion between the nonwoven fabric and the photosensitive drum causes the photosensitive drum to be removed. There is a problem that filming occurs on the surface. Further, in order to prevent such filming, it has been considered to reduce the contact pressure of the nonwoven fabric against the photosensitive drum. However, when pulp fibers harder than the nonwoven fabric are held by the nonwoven fabric, the photosensitive drum is reduced by the pulp fibers. Not only is the surface damaged, but talc is strongly pressed against the photosensitive drum by the accumulated pulp fibers, resulting in a problem of filming. 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 this embodiment, in order to solve the above problems, as shown in FIG. 1, a first paper dust removing means as a first paper dust removing means mainly for removing pulp fibers. Using two types of paper dust removing devices, a paper dust removing device 80 and a second paper dust removing device 90 as a second paper dust removing device mainly for removing filler such as talc, etc. The dust removing device 80 is disposed at a position downstream of the photosensitive drum 20 in the rotation direction with respect to the transfer position where the photosensitive drum 20 and the transfer roller 60 face each other, and the second paper dust removing device 90 is connected to the first paper dust removing device 8.
0 is disposed at a position downstream of the rotation direction in the rotation direction. Hereinafter, the configuration of the paper dust removing means in the present embodiment will be described in detail with reference to FIG.

As shown in FIG. 3, the first paper dust removing device 80
The support member 82 is provided in a case 81 as a paper dust storage member.
And an insulative brush 83 supported by the brush. The brush 83 is in contact with the surface of the photosensitive drum 20 so that the tip of the brush 83 faces the rotation direction of the photosensitive drum 20. The contact position is a position downstream of the transfer position where the photosensitive drum 20 and the transfer roller 60 are opposed to each other in the rotation direction of the photosensitive drum 20 and at which the surface of the photosensitive drum 20 after the transfer can be first contacted. is there. In such a position, paper powder including filler such as talc is attached to the surface of the photosensitive drum 20 together with the pulp fiber.
By 3, hard and long pulp fibers are mainly removed, and the remaining components are conveyed by the photosensitive drum 20 downstream of the contact position in the rotation direction of the photosensitive drum 20. The contact pressure of the brush 83 with the photosensitive drum 20 is set to be extremely small, and the removed pulp fiber is not held by the contact portion, but falls into the storage portion 84 in the case 81 by gravity to be stored. Therefore, a large amount of pulp fiber does not accumulate in the contact portion, and the pulp fiber does not damage the surface of the photosensitive drum 20 and talc filming does not occur.

Next, as shown in FIG. 3, in the second paper dust removing device 90, a nonwoven fabric 92 lined with a sponge 93 is supported by a supporting member 91, and the supporting member 91 is a case of the developing device 50. 51 are integrally attached. In the present embodiment, the nonwoven fabric 92 used is one integrated by confounding 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, polyester fiber, polyamide fiber,
Synthetic fibers such as polyolefin fibers and acrylic fibers,
Or a composite fiber using a resin of each of these fibers, a semi-synthetic fiber such as an acetate fiber, a regenerated fiber such as cupra or rayon, a fiber such as a line, hemp, wool, or a fiber such as a cotton blend. A member is used. Further, in the present invention, the member used for the second paper dust removing means is not limited to a nonwoven fabric, but may be a woven fabric or a knitted fabric.

In the present embodiment, the non-woven fabric 92 is positioned so that the pressing force against the photosensitive drum 20 becomes substantially zero, and the non-woven fabric 92 is lined with a sponge 93 for a long period of time. Photosensitive drum 20
Is maintained at substantially zero. The contact position of the nonwoven fabric 92 with respect to the photosensitive drum 20 is set downstream of the contact position of the first paper dust removing device 80 with the photosensitive drum 20 in the rotation direction of the photosensitive drum 20. Therefore, since the hard pulp fibers contained in the paper dust are reliably removed by the first paper dust removal device 80 as described above, the hard pulp fibers are hard at the contact portion between the nonwoven fabric 92 of the second paper dust removal device 90 and the photosensitive drum 20. No pulp fibers accumulate. As a result, the surface of the photosensitive drum 20 is not damaged by the pulp fiber, and
Of the photosensitive drum 20 is maintained at substantially zero,
In addition, the softness of the material of the nonwoven fabric 92 is not lost. Therefore,
Since a relatively soft filler such as talc captured by the nonwoven fabric 92 is not strongly pressed against the surface of the photosensitive drum 20, filming does not occur. As described above, according to the present embodiment, talc can be reliably removed without damaging the surface of the photosensitive drum 20.

In the case where the nonwoven fabric 92 is fixedly pressed as in this embodiment, paper powder other than pulp fibers accumulates at the contact portion between the nonwoven fabric 92 and the photosensitive drum 20. Is the developing device 50 of the present embodiment.
Is configured as a cartridge that is detachable from the laser beam printer 1, so that the second paper dust removing device 9
By replacing the developing unit 50 with the developing unit 50 integrally, damage to the photosensitive drum 20 such as filming can be prevented for a longer period of time.

As described above, according to this embodiment, by examining the components of the paper dust in detail, the paper dust is divided into a fiber component such as pulp fiber and a filler component such as talc, which is suitable for removing the fiber component. The paper dust removing means is disposed upstream of the visible image carrier in the rotation direction of the paper dust removing means suitable for removing the filler component. Pulp fibers and talc can be reliably removed without causing filming. As a result, pulp fibers and talc are not mixed into the developing device 50, and further, pulp fibers are not transferred to the paper P, so that image defects such as fog or paper stains can be reliably prevented.

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

In the above-described embodiment, the first paper dust removing means is constituted by using a fixed insulating brush.
The configuration shown in FIG. The first shown in FIG.
The paper dust removing apparatus 100 includes an insulating brush made of nylon or the like, having a charge polarity equal to that of the photosensitive drum 20 and a position on the charge series substantially equal to the photosensitive drum 20, on an elastic or rigid roller 101 serving as a support member. A paper dust removal roller 103 to which the paper dust 102 is attached is used. Paper dust removal 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). In the case 104, the brush 102
A scraping member 105 made of PET (polyethylene terephthalate) or the like that comes into contact with the substrate. By using such a first paper dust removing device 100, the photosensitive drum 20
While significantly reducing the pressing force of the brush 102 against
The pulp fibers on the photosensitive drum 20 can be more reliably removed by the wiping force of the brush 102. Even if the pulp fibers adhere to the brush 102, the pulp fibers are not accumulated on the brush 102 because they are scraped off by the scraping member 105.

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. 5 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 60
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, a 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, conductive 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 201 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 in direct contact with the sheet P, not the photosensitive drum 20. Therefore, in this case, the brush 1 of the first paper dust removing device 100 as shown in FIG.
The second paper dust removing means may be configured to contact the nonwoven fabric sheet 112 of the second paper dust removing device 110 as shown in FIG. 7, for example.

Here, the first paper dust removing device 100 is the same as that shown in FIG.
Has the same configuration as the paper dust removing device shown in FIG.

As shown in FIG. 7, the second paper dust removing device 110 includes an elastic or rigid roller 11 as a support member.
1, one end of a strip-shaped nonwoven fabric sheet 112 as a contact member is adhered, and the other end is set as a free end to form a paper dust removing roller 113 so as to overlap with each other. The intermediate transfer belt 201 is rotatably provided and rotated in the same direction as the intermediate transfer belt 201 by a driving unit (not shown). Therefore, at the contact portion with the intermediate transfer belt 201, the nonwoven fabric sheet 112 moves in the counter direction. Further, inside the case 114, a scraping member 115 that comes into contact with the nonwoven fabric sheet 112 and scrapes the paper dust on the nonwoven fabric sheet 112 is attached.

Since the pulp fibers adhering to the intermediate transfer belt 201 are reliably removed on the upstream side by the first paper dust removing device 100 as described above, the second paper dust removing device 1 on the downstream side is used.
Pulp fibers do not accumulate at the contact portions between the ten nonwoven fabric sheets 112 and the intermediate transfer belt 201. Therefore,
Second paper dust removing device 110 for intermediate transfer belt 201
The pressing force of the nonwoven fabric sheet 112 can be significantly reduced, filming can be prevented, and the wiping force of the nonwoven fabric sheet 112 can be applied to the intermediate transfer belt 201.
The upper talc can be reliably removed. This makes it possible to reliably remove the paper dust on the intermediate transfer bell and 201 and prevent image defects.

[0050]

According to the image forming apparatus of the present invention, the fiber component of the paper powder mainly comes into contact with the visible image carrier downstream of the transfer position in the rotation direction of the visible image carrier. A first paper dust removing unit that removes the visible image, and the visible image carrier is disposed downstream of the contact position of the first paper dust removing unit with the visible image carrier in the rotation direction of the visible image carrier. A second paper dust removing unit that comes into contact with the body and mainly removes a filler component of the paper dust, so that the fiber component is placed at the contact position of the second paper dust removing unit with the visible image carrier. The paper dust that is not contained is conveyed, and the accumulation of the fiber component of the paper dust at the contact position can be reliably prevented. Can be reliably removed. That is, according to the present invention, both the fiber component and the filler component of the paper powder can be reliably removed.

According to the image forming apparatus of the second aspect,
A first paper dust removing means including a brush member that comes into contact with the visible image carrier downstream of the transfer position in the rotational direction of the visible image carrier is provided. It can be reliably removed by the member. Further, a nonwoven fabric, a woven fabric, or a non-woven fabric, which comes into contact with the visible image carrier in a rotation direction downstream of the visible image carrier from a contact position of the first paper dust removing unit with the visible image carrier. With the second paper dust removing means including the fiber member made of a knit,
At the contact position of the second paper dust removing means with the visible image carrier,
Paper powder containing no fiber component is conveyed. Therefore, the accumulation of the fiber component of the paper dust at the contact position between the visible image carrier and the fiber member made of a nonwoven fabric, a woven fabric, or a knitted fabric can be reliably prevented, and the filler component of the paper powder due to the accumulated fiber component can be prevented. The filler component of the paper powder can be reliably removed by a fiber member made of a nonwoven fabric, a woven fabric, or a knitted fabric without causing filming. That is, according to the present invention, both the fiber component and the filler component of the paper powder can be reliably removed.

According to the image forming apparatus of the third aspect, since the first paper dust removing means is provided with the roller-shaped brush member, the brush dust removing force of the brush member can be further improved. Thus, the accumulation of the fiber component of the paper dust at the contact position between the second paper dust removing unit and the visible image carrier can be more reliably prevented.

According to the image forming apparatus of the fourth aspect,
The first paper dust removing means comprises a paper dust storage member having an opening, and a brush member fixedly attached to the paper dust storage member, wherein the opening of the paper dust storage member is
Since the paper dust removed by the brush member and dropped by the gravity is formed in a position and a size to be guided inside the paper dust accommodating member, the accumulation of the paper dust in the contact portion between the brush member and the visible image carrier is improved. Can be more reliably prevented, and
The inside of the image forming apparatus can be reliably prevented from being contaminated by paper dust.

According to the image forming apparatus of the fifth aspect,
The developing device is detachable from the image forming apparatus,
Since the second paper dust removing means is attached to the detachable developing device, even if paper dust accumulates at the contact portion between the second paper dust removing means and the visible image carrier, the accumulated paper dust is removed. Damage to the visible image carrier or occurrence of filming due to the powder can be prevented.

According to the image forming apparatus of the sixth aspect,
The transfer residual developer is collected by the developing device and used again for development using a cleaner-less developing method. However, it is possible to reliably prevent paper dust from being mixed into the developing device. Image failure can be reliably prevented.

[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.

3 is a cross-sectional view illustrating a paper dust removing device in the image forming apparatus of FIG.

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

FIG. 5 is a cross-sectional view showing a modification of the usage mode of the paper dust removing device of the present invention.

6 is a cross-sectional view illustrating a first paper dust removing device used in the image forming apparatus of FIG.

FIG. 7 is a sectional view showing a second paper dust removing device used in the image forming apparatus of FIG. 5;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laser beam printer 20 photosensitive drum 80 first paper dust removing device 81 case 82 support member 83 brush member 84 storage section 90 second paper dust removing device 91 support member 92 nonwoven fabric 93 sponge 100 first paper dust removing device 101 brush 102 roller 103 Paper dust removing roller 104 Case 105 Scraping member 110 Second paper dust removing device 111 Roller 112 Nonwoven fabric sheet 113 Paper dust removing roller 114 Case 115 Scraping member

Claims (6)

[Claims] An electrostatic latent image formed on a photoreceptor is developed with a developer to form a visible image, and the visible image is conveyed to a transfer position by a visible image carrier. An image forming apparatus for forming an image by transferring the visible image from an image carrier to a transfer medium, wherein the visible image carrier is disposed downstream of the transfer position in a rotation direction of the visible image carrier. A first paper dust removing unit that comes into contact with the body and mainly removes a fiber component of the paper dust; and a position of the visible image carrier that is higher than a contact position of the first paper dust remover with the visible image carrier. An image forming apparatus comprising: a second paper dust removing unit that comes into contact with the visible image carrier on the downstream side in the rotation direction and mainly removes a filler component of the paper dust. 2. An electrostatic latent image formed on a photoreceptor is developed with a developer to form a visible image, and the visible image is transported to a transfer position by a visible image carrier. An image forming apparatus for forming an image by transferring the visible image from an image carrier to a transfer medium, wherein the visible image carrier is disposed downstream of the transfer position in a rotation direction of the visible image carrier. First including a brush member that contacts the body
Paper dust removing means, and a nonwoven fabric contacting the visible image carrier at a position downstream of the contact position of the first paper dust removing means with the visible image carrier in the rotational direction of the visible image carrier And a second paper dust removing means including a fiber member made of a woven or knitted fabric. 3. The image forming apparatus according to claim 2, wherein the first paper dust removing unit includes a roller-shaped brush member. 4. The paper dust accommodating member includes a paper dust accommodating member having an opening, and a brush member fixedly attached to the paper dust accommodating member. The image forming apparatus according to claim 2, wherein the opening is formed at a position and a size for guiding the paper dust removed by the brush member and dropped by gravity into the inside of the paper dust storage member. . 5. The image forming apparatus according to claim 1, wherein the developing device is detachable from the image forming apparatus, and the second paper dust removing unit is attached to the detachable developing device. The image forming apparatus according to claim 4. 6. The image according to claim 1, wherein a cleaner-less developing system is used in which the transfer residual developer is collected by the developing device and is used again for development. Forming equipment.