JP2003081477A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device offering simplified construction requiring a less number of parts and a smaller size of device while permitting the satisfactory removal of paper dust using a plurality of paper dust removing means. SOLUTION: A first carrying part 9 having a first paper dust removing roller 9b for removing the paper dust from paper 3 and a second carrying part 10 having a second paper dust removing roller 10b are arranged facing to a feed carrier passage 38 and a drop guide passage 39 is formed for guiding to a receiving plane 65 the paper dust removed by the first paper dust removing roller 9b and the second paper dust removing roller 10b. Paper dust storage parts 68 are formed on both sides of the receiving plane 65 in its cross direction and a paper dust carrying plate 66 is provided for carrying the paper dust on the receiving plane 65 to the paper dust storage part 68. The paper dust dropped in the drop guide passage 39 by its dead weight and stored on the receiving plane 65 is carried to the paper dust storage part 68 by the paper dust carrying plate 66 and stored in a lump.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a laser printer.

[0002]

2. Description of the Related Art In an image forming apparatus such as a laser printer, usually, a sheet feeding mechanism such as a sheet feeding cassette in which sheets are stacked in a stack, and an image forming mechanism for forming an image on the fed sheets. Is equipped with.

The paper feed mechanism usually includes a paper feed tray on which a paper is placed, and a paper feed roller and a paper feed pad which are provided above one end of the paper feed tray and are arranged to face each other. The paper on the paper feed tray is sandwiched between the paper feed roller and the paper feed pad by the rotation of the paper feed roller to feed the paper one by one.

Further, the image forming mechanism is provided with a photosensitive drum, and a charger, a scanner device, a developing roller and a transfer roller around the photosensitive drum in order according to the rotation direction of the photosensitive drum. As the photosensitive drum rotates, the surface of the photosensitive drum is first uniformly charged by a charger, and then exposed by high-speed scanning of a laser beam from a scanner device, and electrostatically based on predetermined image data. A latent image is formed, and then, by the rotation of the developing roller, the toner carried on the developing roller is supplied to the electrostatic latent image formed on the surface of the photosensitive drum and selectively carried. To form a visible image. Then, the visible image carried on the surface of the photosensitive drum is transferred onto the paper while the paper fed from the paper feeding mechanism passes between the photosensitive drum and the transfer roller, whereby a predetermined image is formed on the paper. Image is formed.

In such an image forming apparatus, since the paper is fed one by one while being sandwiched between the paper feed roller and the paper feed pad, the paper is rubbed against the paper feed pad and the like. The generation of powder is unavoidable, and if such paper powder mixes in the toner in the image forming mechanism, there arises a problem that image quality is deteriorated.

Therefore, for example, in order to remove the paper dust of the paper fed from the paper feed mechanism, there is known a paper feed path provided with a plurality of paper dust removing rollers.

[0007]

However, in a device provided with such a plurality of paper dust removing rollers,
The paper dust removed by each paper dust removing roller is transported and stored for each paper dust removing roller, and a transport mechanism and a storage space are required for each paper dust removing roller, which complicates the device configuration, This leads to an increase in points and inevitably increases the size of the device.

Therefore, the present invention has been made in view of such circumstances, and an object of the present invention is to make it possible to remove paper dust satisfactorily by a plurality of paper dust removing means, and to use the apparatus. An object of the present invention is to provide an image forming apparatus capable of simplifying the configuration, reducing the number of parts, and downsizing the apparatus.

[0009]

In order to achieve the above object, the invention described in claim 1 is a paper dust removing means for removing paper dust of a recording medium supplied to an image forming means, and the paper. In an image forming apparatus provided with a paper dust storage unit for storing the paper dust removed by the dust removing unit, the paper dust removing unit is provided in a plurality of supply conveyance paths for supplying a recording medium to the image forming unit. The image forming apparatus is provided, and the paper dust storage unit is configured to collectively store the paper dust removed by each of the plurality of paper dust removing units.

According to this structure, since the respective paper dusts removed by the plurality of paper dust removing means are collectively stored in the paper dust storing section, it is not necessary to store each paper dust removing means. In addition, the device configuration can be simplified, the number of parts can be reduced, and the device can be downsized.

The invention described in claim 2 is the same as claim 1.
In the invention described in, the paper dust storage unit is provided below each of the paper dust removing means, to store the paper dust falling by its own weight after being removed by each paper dust removing means, It has a feature.

According to this structure, the paper dusts removed by the plurality of paper dust removing means are dropped by their own weight and are stored in the paper dust storage unit at once.
Therefore, with a simple configuration, the paper dust removed by each paper dust removing means can be stored in the paper dust storage unit at once.

The invention described in claim 3 is the same as that of claim 2
In the invention described in (3) above, there is provided a drop guide passage for guiding the paper powder falling by its own weight after being removed by the paper powder removing means.

According to this structure, the paper dusts removed by the plurality of paper dust removing means are guided by being dropped in the drop guide passage by their own weight, and are collectively stored in the paper dust storing section. . Therefore, the paper dust removed by each paper dust removing means can be guided by a simple configuration and stored in a batch in the paper dust storage unit.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the paper dust removed by each paper dust removing means is conveyed toward the paper dust storing section. It is characterized in that it is provided with a paper powder conveying means for.

According to this structure, the paper dusts removed by the plurality of paper dust removing means are conveyed toward the paper dust storing section by the paper dust conveying means. Therefore, with a simple configuration, the paper dust removed by each paper dust removing means can be transported and stored in a batch, which further simplifies the device configuration, reduces the number of parts, and downsizes the device. Can be realized.

The invention described in claim 5 is the same as claim 3
Alternatively, in the invention described in 4, the supply transport path is
A guide plate for guiding the recording medium is provided, and the drop guide passage is formed by the back side of the guide plate.

According to this structure, since the drop guide passage is formed by utilizing the back surface of the guide plate of the supply / conveyance path, the structure of the device is further simplified, the number of parts is reduced, and the device is further reduced. The size can be reduced.

The invention according to claim 6 is the same as claim 5
In the invention described in (1), the guide plate is provided with an extending portion that covers at least the upper part of the paper dust removing means arranged below.

With such a construction, even if the paper dust removed by the paper dust removing means arranged above the paper dust removing means arranged below the paper dust removing means,
The extending portion can effectively prevent the paper dust from falling on the paper dust removing means arranged below the extending portion.
Therefore, good paper dust removing operation of each paper dust removing means arranged below can be ensured for a long period of time.

The invention described in claim 7 is the same as claim 1.
In the invention described in any one of 1 to 6, each of the paper dust removing means includes a paper dust removing member that contacts the recording medium to remove the paper dust, and a paper dust removing member that faces the paper dust removing member. And a scraping member for scraping off the paper dust adhering to the member.

According to this structure, in each paper dust removing means, the paper dust removing member first contacts the recording medium to remove the paper dust on the recording medium, and then the paper dust removing member The attached paper dust is scraped off by the scraping member. As a result, the paper dust removing performance of the paper dust removing member is maintained, so that each paper dust removing means can achieve good paper dust removal over a long period of time.

The invention described in claim 8 is the invention according to claim 7.
In the invention according to, in each of the paper dust removing means,
The paper dust removing member is configured to be movable in the same direction as the conveyance direction of the recording medium in a portion facing the supply / conveyance path, and the scraping member is configured to supply / convey the paper dust removing member to / from the paper dust removing member. It is characterized in that it is configured to scrape the paper dust below the opposite side of the path.

According to such a structure, the paper dust removing member first comes into contact with the recording medium along with its movement to remove the paper dust on the recording medium, and then adheres to the paper dust removing member. The paper dust is scraped off by the scraping member below the paper dust removing member on the opposite side of the supply transport path. As a result, the paper dust scraped by the scraping member stays on the lower side of the opposite side of the supply / conveyance route and then falls, so that the scraped paper dust is effectively prevented from entering the supply / conveyance route. At the same time, the paper dust removed by each paper dust removing means can be stored collectively.

The invention described in claim 9 is the same as claim 1.
In the invention described in any one of (1) to (8), the plurality of paper dust removing means are arranged vertically on one side of the supply transport path to which a recording medium is supplied.

According to this structure, since the plurality of paper dust removing means are vertically arranged on one side of the supply / conveyance path, the paper dust removed by each paper dust removing means and falling due to its own weight is kept as it is. It can be collected in one place, and can be collectively stored with a simpler configuration.

According to a tenth aspect of the present invention, in the invention according to any one of the seventh to ninth aspects, a separating pad and a supply roller are provided to supply the recording medium to the supply conveyance path. By reversing the front and back of the recording medium having an image formed on one surface by the image forming unit,
And a re-conveyance path for conveying the recording medium again toward the image forming unit, wherein the downstream end of the re-conveyance path is connected in the middle of the supply conveyance path. The first paper dust removing unit is provided on the upstream side in the conveying direction of the recording medium with respect to the connecting portion of the re-conveying path, and on the downstream side in the conveying direction of the recording medium with respect to the connecting portion. A paper dust removing means is provided, and the paper dust removing member of the first paper dust removing means has a width that is at least wider than the separation pad width of the separation pad in the direction orthogonal to the conveyance direction of the recording medium, The paper dust removing member of the second paper dust removing means has a width that is at least wider than the width of the recording medium in the direction orthogonal to the conveying direction of the recording medium.

According to this structure, at least the paper dust of the portion corresponding to the separation pad width of the recording medium fed by the feeding means is first removed by the paper dust removing member of the first paper dust removing means. After that, the paper dust removing member of the second paper dust removing unit removes the paper dust in the portion corresponding to the recording medium width. Therefore, a larger amount of paper dust generated by rubbing with the separation pad is removed by the first paper dust removing unit and the second paper dust removing unit, and the recording medium is originally cut when the recording medium is cut. A smaller amount of paper dust generated throughout is removed by the second paper dust removing means. Therefore, the paper dust generated by rubbing between the separation pad and the paper dust originally generated,
It is possible to remove in a well-balanced manner, and it is possible to achieve uniform removal of paper dust with less uneven removal.

On the other hand, in the recording medium re-conveyed by the re-conveying means, the paper dust is not removed by the first paper dust removing means, but since the front and back are reversed, only the second paper dust removing means is used. Efficient removal of paper dust can be achieved by removing paper dust. Therefore, the first paper dust removing means and the second paper dust removing means can efficiently achieve appropriate paper dust removal according to the adhered state of the paper dust.

The eleventh aspect of the invention is the invention according to any one of the first to tenth aspects, wherein the image forming means forms a visible image formed by developing the electrostatic latent image. It is characterized in that it is constituted by an electrophotographic system in which an image is formed by transferring it onto a recording medium.

In the electrophotographic system in which an electrostatic latent image is developed to form a visible image and is transferred to a recording medium, if paper dust is present on the recording medium, the paper dust forms an image during transfer. It is particularly necessary to remove the paper dust on the recording medium because it gets mixed into the means, but according to such a configuration,
Since the paper dust on the recording medium can be efficiently removed by the plurality of paper dust removing means, good image formation can be surely achieved by the electrophotographic method.

According to a twelfth aspect of the invention, in the invention according to the eleventh aspect, the image forming means includes a photoconductor on which an electrostatic latent image is formed and a developing means for supplying a developer. A non-magnetic one-component developer is used as the developer, and cleanerless development is performed in which the developer remaining on the photoconductor after transfer is collected by a developing means. It is characterized by being.

In the electrophotographic system, if cleanerless development is carried out by using a non-magnetic one-component developer, no special member and reservoir for removing the developer remaining on the photoreceptor after transfer is required. Therefore, the device configuration can be simplified. However, on the other hand, in cleanerless development,
Since the developer remaining on the photoconductor after the transfer is collected by the developing means, if the paper dust from the recording medium adheres to the photoconductor during the transfer, the paper dust will be mixed in the developing means together with the collected developer. However, there is a problem that it directly affects the image quality.

However, according to this structure, the paper dust on the recording medium can be efficiently removed by the plurality of paper dust removing means, so that the developer can be easily collected by the cleanerless development, Good image formation can be reliably achieved.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a side sectional view of an essential part showing an embodiment of a laser printer as an image forming apparatus of the present invention. In FIG. 1, the laser printer 1 is configured as a laser printer that forms an image by an electrophotographic method, and a main body casing 2 is provided with a feeder unit 4 for feeding a paper 3 as a recording medium and a feeding unit. The image forming unit 5 is provided as an image forming unit for forming a predetermined image on the printed sheet 3.

The feeder unit 4 includes a paper feed tray 6 which is removably mounted on the bottom of the main body casing 2, and a paper feed mechanism unit 7 as a feeding means provided at one end of the paper feed tray 6. , A paper pressing plate 8 provided in the paper feeding tray 6
And is provided on the downstream side in the transport direction of the sheet 3 with respect to the sheet feeding mechanism unit 7 (hereinafter, the upstream side or the downstream side in the transport direction of the sheet 3 may be simply referred to as the upstream side or the downstream side). First as a paper dust removing means (first paper dust removing means)
The transport unit 9 and the second transport unit 10 as a paper dust removing unit (second paper dust removing unit), and the resist provided on the downstream side in the transport direction of the paper 3 with respect to the first transport unit 9 and the second transport unit 10. And a roller 11.

The paper feed tray 6 has a box shape with an open upper surface capable of accommodating the paper 3, and is attachable to and detachable from the bottom of the main body casing 2 in the horizontal direction.

The paper feed mechanism section 7 includes a paper feed roller 12 as a feed roller, and a separation pad 13 facing the paper feed roller 12. As shown in FIG. 2, the separation pad 13 includes a support frame 13a, a pad member 13b, and a spring 13c.

The support frame 13a is provided with a flat plate-like member that faces below the paper feed roller 12, and a support member that is bent downward in a substantially orthogonal direction from one end of the flat plate member. It is formed as a V-shaped member, and the lower end portion of the support member is swingably supported.
A pad member 13b is embedded on the surface of the flat plate member facing the paper feed roller 12, and a spring 13c is arranged on the back side thereof, and the pad member 13b is pressed against the paper feed roller 12 by the spring 13c. Is urged to.

The pad member 13b, as shown in FIG.
The pad member 13 has a substantially rectangular plate shape, is made of an elastic member such as urethane rubber, and is in a direction orthogonal to the conveyance direction of the paper 3.
The width B of b (hereinafter, the width in the direction orthogonal to the transport direction of the sheet 3 may be simply referred to as the width) is the width A of the sheet 3 (the maximum sheet 3 that can be printed by the laser printer 1).
The width is smaller than the width. That is, the pad member 13b is formed to have a width that comes into contact with only the central portion in the width direction of the sheet 3 for sheet feeding.

As shown in FIG. 1, the sheet pressing plate 8 is capable of stacking sheets 3 in a stacked form and is swingably supported at the end portion far from the sheet feeding roller 12. The near end is movable in the vertical direction, and is urged upward from the back side by a spring (not shown). Therefore, as the stacking amount of the sheets 3 increases, the sheet pressing plate 8 swings downward against the biasing force of the spring with the end portion farther from the sheet feeding mechanism section 7 as a fulcrum. Then, the topmost sheet 3 on the sheet pressing plate 8
Is pressed from the back side of the paper pressing plate 8 toward the paper feeding roller 12 by a spring (not shown).
After being sandwiched between the sheet feeding roller 12 and the pad member 13b by the rotation of the sheet, the sheets are separated and fed sheet by sheet in cooperation with each other. The fed paper 3 is fed to a first feed unit 9 and a second feed unit 9 which will be described later, in a feed feed route 38 as a feed transport route for the paper 3 between the feed mechanism unit 7 and the image forming unit 5.
It is sent to the registration roller 11 by the carrying unit 10. The registration roller 11 is composed of a pair of rollers, and is configured to send the sheet 3 to the image forming unit 5 after a predetermined registration.

The image forming section 5 includes a scanner section 17, a process section 18, a fixing section 19 and the like.

The scanner section 17 is provided in the upper portion of the main body casing 2, and has a laser emitting section (not shown), a polygon mirror 20 which is driven to rotate, and lenses 21a and 21.
b, a reflecting mirror 22 and the like, and emits a laser beam based on predetermined image data emitted from the laser emitting section,
As indicated by the chain line, the polygon mirror 20 and the lens 21
A, the reflecting mirror 22, and the lens 21b are passed or reflected in this order, and the surface of the photosensitive drum 23 of the process unit 18 described later is irradiated with the light at high speed scanning.

The process section 18 is disposed below the scanner section 17 and is detachably attached to the main body casing 2. This process unit 18
Photosensitive drum 23 as a photoconductor and developing cartridge 2
4, a transfer roller 25, and a scorotron type charger 37. The developing cartridge 24 is the process unit 1
8 is detachably attached to the toner container 2
6, a developing roller 27 as a developing means, a layer thickness regulating blade 28, a toner supply roller 29 and the like.

The toner accommodating portion 26 is filled with positively charged non-magnetic one-component polymerized toner as a developer,
The toner is supplied to the developing roller 27 by the toner supply roller 29, and is further carried on the developing roller 27 as a thin layer having a constant thickness by the rubbing of the layer thickness regulating blade 28. On the other hand, the photosensitive drum 23 is rotatably arranged so as to face the developing roller 27, the drum body is grounded, and the surface thereof is formed of a positively chargeable photosensitive layer made of polycarbonate or the like. There is.

The surface of the photosensitive drum 23 is uniformly positively charged by the scorotron charger 37 as the photosensitive drum 23 rotates in the direction of the arrow, and then the high speed of the laser beam from the scanner unit 17 is reached. Exposed by scanning,
An electrostatic latent image is formed on the basis of predetermined image data, and thereafter, when facing the developing roller 27, toner carried on the developing roller 27 and positively charged is formed on the surface of the photosensitive drum 23. An electrostatic latent image, that is, a surface of the photosensitive drum 23 that is uniformly positively charged is supplied to a portion of the surface of the photosensitive drum 23 that is exposed by a laser beam and has a reduced potential, and is selectively carried to form a visible image. And thus reversal development is achieved.

The transfer roller 25 is arranged below the photosensitive drum 23 so as to face the photosensitive drum 23. The transfer roller 25 has a metal roller shaft covered with a roller made of a conductive rubber material, and a predetermined transfer bias is applied to the photosensitive drum 23. Therefore, the visible image carried on the photosensitive drum 23 is transferred to the paper 3 while the paper 3 passes between the photosensitive drum 23 and the transfer roller 25. The sheet 3 on which the visible image is transferred is conveyed to the fixing unit 19 via the conveying belt 30.

The fixing section 19 is disposed on the downstream side of the process section 18, and is provided on the heating roller 31, the pressing roller 32 for pressing the heating roller 31, and the downstream side of the heating roller 31 and the pressing roller 32. Conveyor roller 3
Equipped with 3.

The heating roller 31 is made of metal and is provided with a halogen lamp for heating. The paper 3 heats the toner transferred onto the paper 3 in the process section 18.
1 is fixed by heat while passing between 1 and the pressing roller 32,
After that, the sheet 3 is conveyed by the conveying roller 33 of the fixing unit 19 to the conveying roller 34 and the sheet discharging roller 35 provided in the main body casing 2. The paper 3 sent to the transport roller 34 is then discharged to the paper discharge roller 35.
Then, the paper is discharged onto the paper discharge tray 36.

In the laser printer 1, the photosensitive drum 2 is transferred after being transferred onto the paper 3 by the transfer roller 25.
The residual toner remaining on the surface of No. 3 is collected by the developing roller 27, that is, the so-called cleanerless developing method. If the residual toner is collected by such a cleanerless developing method, a special member such as a blade for removing the residual toner and a waste toner storage portion are not required, and the apparatus configuration can be simplified.

Further, in this laser printer 1, the paper 3
Re-conveying unit 41 for forming images on both sides of The re-conveying unit 41 includes a reversing mechanism section 42.
And the re-conveying tray 43 are integrally formed, and the re-conveying tray 43 is inserted above the feeder section 4 while the reversing mechanism section 42 is externally attached from the rear side of the main body casing 2. In this state, it is detachably attached.

The reversing mechanism portion 42 is externally attached to the rear wall of the main body casing 2, has a casing 44 having a substantially rectangular cross section, and is provided with a flapper 45, a reversing roller 46 and a re-conveying roller 47, and a reversing guide from the upper end portion. Plate 48
Is projected upward.

The flapper 45 is rotatably supported at the rear portion of the main body casing 2, is disposed in the vicinity of the downstream side of the conveying roller 33, and an image is formed on one surface by exciting or de-exciting a solenoid (not shown). The paper 3 conveyed by the conveyance roller 33 is conveyed by the conveyance roller 3
4 is provided so as to be swingable so as to be selectively switchable between a direction (solid line state) and a direction (virtual line state) which will be described later.

The reversing roller 46 is disposed on the downstream side of the flapper 45 and above the casing 44, and is composed of a pair of rollers, and is configured so that the rotation can be switched between the forward direction and the reverse direction. The reversing roller 46 is
First, the sheet 3 is rotated in the forward direction so that the sheet 3 is reversed to the guide plate 4.
8 and then rotate in the opposite direction to feed paper 3
Can be conveyed in the reverse direction.

The re-conveying roller 47 is on the downstream side of the reversing roller 46, and the reversing roller 46 in the casing 44.
The sheet 3 which is arranged almost immediately below the sheet and which is composed of a pair of rollers and which is reversed by the reversing roller 46
It is configured so that it can be transported to the No. 3 station.

The reversing guide plate 48 is a plate-like member extending further upward from the upper end portion of the casing 44, and the paper 3 fed by the reversing roller 46.
Is configured to guide.

When images are to be formed on both sides of the paper 3, the flapper 45 is first switched in the reversing mechanism section 42 so as to direct the paper 3 toward the reversing roller 46, and the reversing mechanism section 42 is turned on. Then, the sheet 3 having the image formed on one surface is received. After that, when the accepted sheet 3 is sent to the reversing roller 46,
The reversing roller 46 rotates normally with the paper 3 being sandwiched,
The sheet 3 is once conveyed upward and outward along the reversing guide plate 48, most of the sheet 3 is sent upward and upward, and when the rear end of the sheet 3 is nipped by the reversing roller 46,
Stop forward rotation. Next, the reversing roller 46 rotates in the reverse direction, and conveys the sheet 3 to the re-conveying roller 47 in a state in which the sheet 3 is reversed in the front-rear direction so as to face substantially right below. The timing for rotating the reverse roller 46 from the forward rotation to the reverse rotation is
A paper passage sensor 56 provided on the downstream side of the fixing unit 19.
However, it is controlled so that a predetermined time elapses after the trailing edge of the sheet 3 is detected. In addition, the flapper 45
When the conveyance of the sheet 3 to the reversing roller 46 is finished, the original state, that is, the sheet 3 sent from the conveying roller 33 is
Is switched to a state where it is sent to the transport roller 34.

Next, the sheet 3 conveyed in the reverse direction to the re-conveyance roller 47 is moved by the re-conveyance roller 47.
It is transported to the re-transport tray 43 described below.

The re-conveyance tray 43 includes a sheet supply section 49 to which the sheet 3 is supplied, a tray body 50 and a skew roller 51.
Is equipped with.

The sheet supply section 49 is externally attached to the rear portion of the main body casing 2 below the reversing mechanism section 42, and includes a curved sheet guide member 52. This paper supply unit 4
In FIG. 9, the sheet 3 fed in the substantially vertical direction from the re-conveyance roller 47 of the reversing mechanism unit 42 is guided in the substantially horizontal direction by the sheet guide member 52 and is moved in the substantially horizontal direction toward the tray main body 50. I try to send it out.

The tray main body 50 has a substantially rectangular plate shape and is provided in a substantially horizontal direction above the paper feed tray 6. The upstream end of the tray main body 50 is connected to the paper guide member 52, and The downstream end is the second from the tray main body 50.
In order to guide the sheet 3 to the transport unit 10, the downstream end thereof is connected to the re-transport path 53 which is connected in the middle of the sheet transport path 38.

Further, in the middle of the tray body 50 in the conveying direction of the sheet 3, a skew roller 51 for conveying the sheet 3 while abutting against a reference plate (not shown) is provided with a predetermined interval in the conveying direction of the sheet 3. Are separated by two.

The skew rollers 51 are arranged in the vicinity of a reference plate (not shown) provided on one end of the tray body 50 in the width direction, and the skew rollers 51 are arranged so that their axes are substantially orthogonal to the conveying direction of the sheet 3. The drive roller 54 and the skew drive roller 54 face each other with the sheet 3 interposed therebetween, and the axis of the drive roller 54 is inclined from the direction substantially orthogonal to the transport direction of the sheet 3 toward the reference plane. And a slanted driven roller 55 arranged in the direction.

Then, the tray main body 5 is fed from the paper feeding section 49.
The sheet 3 sent to 0 is fed by the skew roller 51.
While one widthwise end edge of the sheet 3 is in contact with the reference plate,
It is conveyed toward the image forming unit 5 via the re-conveyance path 53 with the front and back reversed. Then, the rear surface of the sheet 3 conveyed to the image forming section 5 is brought into contact with the photosensitive drum 23 so that the visible image is transferred thereto, and then the fixing section 1 is transferred.
In the state where it is fixed in 9 and images are formed on both sides,
The paper is discharged onto the paper discharge tray 36.

Then, in the laser printer 1, as shown in FIG.
The paper dust originally generated on the entire paper 3 and the paper dust generated on the surface of the paper 3 due to the rubbing between the pad member 13 b of the paper feed mechanism unit 7 and the paper feed roller 12 are used.
First transport section 9 and second transport section 10 arranged in
Is configured so that it can be removed in a balanced manner.

The first conveying section 9 is on the front side of the sheet feeding / conveying path 38, downstream of the sheet feeding roller 12 of the sheet feeding mechanism section 7 in the conveying direction of the sheet 3, and the sheet feeding / conveying path 38. In the upstream side of the connection portion of the re-conveyance path 53 with the downstream end portion, the first conveyance roller 9a that is arranged at a predetermined distance from the paper feed roller 12 and conveys the paper 3, and the paper feed roller 9a. The first transport roller 9 with the transport path 38 in between.
a first paper dust removing roller 9b as a paper dust removing member which is arranged to face a, and a first sponge member 9c as a scraping member which is placed below the first paper dust removing roller 9b. There is.

The first conveying roller 9a is connected to the paper feeding / conveying path 38.
The metal roller shaft 9d is covered with a rubber roller 9e, and power from a motor (not shown) is transmitted to the arrow direction (clockwise in FIG. 1).
It is configured to be driven to rotate.

The first paper dust removing roller 9b faces the paper feeding / conveying path 38 from the outside, and has a metal roller shaft 9f whose surface is electrically charged, such as a roller made of fluororesin or a roller whose surface is coated with fluorine. Rubber roller 9
g are coated. The first paper dust removing roller 9b is
As shown in FIG. 3, the surface of the paper 3 fed by the paper feed roller 12 that is in contact with the pad member 13b (photosensitive drum 2
3 is arranged at a substantially central portion with respect to the first conveying roller 9a overlapping the separating pad 13 in the conveying direction of the sheet 3 so as to come into contact with the contact portion of the pad member 13b on the image forming surface (which is in contact with 3). The width of 9g is
It is formed to be narrower than the width of the roller 10g of the second paper dust removing roller 10b, which will be described later, and slightly wider than the width B of the pad member 13b.

The first paper dust removing roller 9b is driven by the first conveying roller 9a in the direction of the arrow, that is, in the same direction as the conveying direction of the sheet 3 in the portion facing the sheet feeding conveying path 38 (in FIG. 1, FIG. 1). It is driven to rotate in the counterclockwise direction, and while removing the paper dust of the paper 3, the paper 3 is sandwiched between the first transport roller 9a and the first paper dust removing roller 9b to transport the paper 3. ing.

As shown in FIG. 2, the first sponge member 9c is made of a material such as urethane foam that easily charges the first paper dust removing roller 9b.
On the other hand, the first paper dust removing roller 9b is arranged so that the paper dust can be scraped off below the opposite side of the paper feed / conveyance path 38.
Is arranged so as to be in pressure contact with the first paper dust removing roller 9b, scrapes away the paper dust adhering to the first paper dust removing roller 9b, and removes the first paper dust removing roller 9b.
By rubbing against the roller 9 of the first paper dust removing roller 9b.
g surface is triboelectrically charged. Also,
The width of the first paper dust removing roller 9b is as shown in FIG.
It is formed slightly wider than the width of the roller 9g.

As shown in FIG. 2, the second transport section 10 is located above the first transport section 9 on the front side of the paper feed transport path 38 and is downstream of the first transport section 9 in the transport direction of the sheet 3. And the re-conveyance path 5 in the paper feed / conveyance path 38.
A second conveyance roller 10a that conveys the sheet 3 and that is arranged in the vicinity of the downstream side of the connection portion of the sheet 3 with the downstream side end portion;
The second paper dust removing roller 1 as a paper dust removing member that is arranged to face the second transport roller 10a with the paper feed transport path 38 interposed therebetween.
0b and a second sponge member 10 as a scraping member that is arranged below the second paper dust removing roller 10b so as to face each other.
and c.

The second conveying roller 10a is connected to the paper feeding / conveying path 3.
8, a metal roller shaft 10d is covered with a rubber roller 10e, and is rotated in the arrow direction (clockwise in FIG. 1) by transmitting power from a motor (not shown). Is configured.

The second paper dust removing roller 10b faces the paper feed / conveyance path 38 from the outside, and has a metal roller shaft 10f, such as a roller made of fluororesin or a roller whose surface is fluorine-coated, whose surface is charged. It is covered with a rubber roller 10g which is easily damaged. This second paper dust removing roller 1
As shown in FIG. 3, the roller 0b is arranged to contact the entire surface of the paper 3 fed by the paper feed roller 12 in contact with the pad member 13b (image forming surface in contact with the photosensitive drum 23). The width of 10 g is formed to be slightly wider than the width A of the paper 3.

The second paper dust removing roller 10b is
As shown in FIG. 3, power from a motor (not shown) is input from an input gear 10h provided at one end of the roller shaft 10f of the second paper dust removing roller 10b, whereby the power is supplied in the direction of the arrow, that is, the paper feed / transport path. It is configured to be driven to rotate in the same direction as the conveyance direction of the paper 3 (counterclockwise in FIG. 1) in the portion facing 38, and while removing the paper dust of the paper 3, the second conveyance roller 10a and the second conveyance roller 10a are removed. The paper 3 is sandwiched between the two paper dust removing rollers 10b, and the paper 3 is conveyed.

The second sponge member 10c is made of a material such as urethane foam that easily charges the second paper dust removing roller 10b, and the paper is provided below the second paper dust removing roller 10b on the opposite side of the paper feeding / conveying path 38. The second paper dust removing roller 10b is arranged below the second paper dust removing roller 10b so as to be able to scrape off the powder so as to be pressed against the second paper dust removing roller 10b. The roller 10 of the second paper dust removing roller 10b is scraped off and rubbed against the second paper dust removing roller 10b.
g surface is triboelectrically charged. Also,
The width of the second paper dust removing roller 10 is as shown in FIG.
It is formed slightly wider than the width of b.

In this laser printer 1, the sheets 3 stacked in the sheet feed tray 6 are
1 by the cooperation of the paper feed roller 12 and the separation pad 13.
Each sheet is separately fed, but at the time of feeding, a large amount of paper dust is generated on the image forming surface due to the friction with the separating pad 13. However, when the sheet 3 is first conveyed to the first conveying section 9, when the sheet 3 is conveyed while being sandwiched between the first conveying roller 9a and the first paper dust removing roller 9b, its image forming surface is The paper dust removing roller 9b comes into contact with the roller 9g. Then, since the first paper dust removing roller 9b is formed slightly wider than the width of the separating pad 13, the pad member 1 on the paper 3 is rubbed against the separating pad 13.
The paper dust generated with a width substantially equal to the width of 3b is scraped off by the roller 9g of the first paper dust removing roller 9b and electrostatically adsorbed. Then, the paper dust adhered to the roller 9g of the first paper dust removing roller 9b is then scraped by the first sponge member 9c when the first paper dust removing roller 9b is rotated to face the first sponge member 9c. Taken.

Next, when the sheet 3 is conveyed to the second conveying section 10, the second conveying roller 10a and the second paper dust removing roller 1
0b, the image forming surface is
It contacts the roller 10g of the second paper dust removing roller 10b.
Then, since the second paper dust removing roller 10b is formed slightly wider than the width of the paper 3, the paper dust originally generated on the entire paper 3 at the time of cutting the paper 3,
Also, the paper dust removed and left by the first paper dust removing roller 9b is scraped off by the roller 10g of the second paper dust removing roller 10b and electrostatically adsorbed. The paper dust attached to the roller 10g of the second paper dust removing roller 10b is then rotated by the second paper dust removing roller 10b.
When facing the second sponge member 10c, it is scraped off by the second sponge member 10c.

Therefore, in the laser printer 1, the paper 3 fed by the paper feed mechanism 7 is the image forming unit 5
By the first paper dust removing roller 9b,
The paper dust of the portion corresponding to the width B of the pad member 13b is removed, and the paper dust of the portion corresponding to the width A of the paper 3 is removed by the second paper dust removing roller 10b.

As a result, a larger amount of paper dust generated by rubbing with the pad member 13b is removed by the first paper dust removing roller 9b and the second paper dust removing roller 10b, and at the time of cutting the paper 3. For example, a smaller amount of paper dust originally generated over the entire sheet 3 is removed by the second paper dust removing roller 10b. As a result, the paper powder generated by the rubbing between the pad member 13b and the paper powder originally generated can be removed in a well-balanced manner by the first transfer unit 9 and the second transfer unit 10, and the unevenness of the removal can be achieved. It is possible to achieve uniform removal of paper dust with less waste. Therefore, in this laser printer 1, it is possible to effectively prevent the mixing of paper dust into the image forming section 5, and to form an image of high quality.

Further, since the second paper dust removing roller 10b is arranged on the downstream side of the first paper dust removing roller 9b in the conveying direction of the paper 3, the paper 3 fed by the paper feeding mechanism section 7 is provided. First, after the first paper dust removing roller 9b removes a larger amount of paper dust caused by the rubbing between the pad member 13b and the second paper dust removing roller 10b, A smaller amount of paper dust originally generated over the entire sheet 3 when the sheet 3 is cut is removed. Therefore, it is possible to achieve efficient removal of the paper dust based on the difference in the amount of the paper dust, so that it is possible to achieve even more uniform removal of the paper dust.

The second paper dust removing roller 10b has a width larger than the width of the paper 3, while the first paper dust removing roller 9b is wider than the width of the separating pad 13 and the second paper dust removing roller 9b.
Since the paper dust removing roller 10b has a width narrower than that of the paper dust removing roller 10b, the paper dust can be removed in a balanced manner without unnecessarily increasing the width of the first paper dust removing roller, and the cost is reduced. be able to.

As described above, in this laser printer 1, the paper 3 is separated from the paper feed roller 12 by a predetermined distance so that the first paper dust removing roller 9b does not come into contact with the paper feed roller 12. Is arranged on the upstream side in the transport direction of.

For example, when the first paper dust removing roller 9b is in contact with the paper feed roller 12, the paper 3 to be fed next is slid between the paper feed roller 12 and the separation pad 13, The laser printer 1 is pulled out slightly following the paper 3 that has already been fed, and the leading end portion of the paper 3 is sandwiched between the paper feed roller 12 and the first paper dust removing roller 9b, and in that state. When the sheet is stopped, a curl-like habit may be attached to the leading end portion of the sheet 3 sandwiched between the sheet feeding roller 12 and the first sheet dust removing roller 9b. In such a case, the next time the paper 3 is supplied, it may cause a jam, or image drooling may occur at the curled tip portion.

However, if the first paper dust removing roller 9b is arranged so as not to contact the paper feed roller 12, the paper 3 to be fed next is already fed. Even if the paper 3 is pulled out a little following the formed paper 3, it is not pinched between the paper feed roller 12 and the first paper dust removing roller 9b, and a curl-like habit is formed at the leading end of the paper 3. Can be prevented. Therefore, it is possible to always achieve good sheet feeding while achieving good removal of paper dust.

Further, the first transfer section 9 and the second transfer section 10
The first paper dust removing roller 9b, the first paper dust removing roller 9b
A first sponge member 9c for scraping off the paper dust attached to the paper dust removing roller 9b is provided, and the second sponge removing roller 10b faces the second paper dust removing roller 10b.
Second sponge member 10 for scraping off paper dust adhering to the
Since c is provided, the paper dust attached to the first paper dust removing roller 9b and the second paper dust removing roller 10b is scraped off by the first sponge member 9c and the second sponge member 10c, respectively. The paper dust removing performance of the paper dust removing roller 9b and the second paper dust removing roller 10b can be maintained, and good paper dust removal can be achieved over a long period of time.

The widths of the first sponge member 9c and the second sponge member 10c are formed to be slightly wider than the widths of the first paper dust removing roller 9b and the second paper dust removing roller 10b which face each other. Paper 3
Even if the above paper dust spreads slightly in the width direction due to the contact with the first paper dust removing roller 9b and the second paper dust removing roller 10b, it can be scraped well.

Further, in the laser printer 1, the paper 3 fed by the paper feed mechanism section 7 is first sandwiched between the first paper dust removing roller 9b and the first transport roller 9a,
The paper dust is conveyed while being removed, and is then sandwiched between the second paper dust removing roller 10b and the second conveying roller 10a to be conveyed while removing the paper dust. While achieving the above, it is possible to secure good conveyance of the sheet 3 to reach the image forming unit 5.

Moreover, since the second paper dust removing roller 10b is not driven by the second conveying roller 10a, but is driven by a motor (not shown) via the input gear 10h, the second paper dust removing roller 10b is not driven. Taking roller 10b
Can be driven by itself. Therefore, the second
Even if the paper 3 or the second sponge member 10c comes into contact with the entire roller 10g of the paper dust removing roller 10b and a load torque is applied, the second paper dust removing roller 10 is driven by itself.
Good rotation of b can be ensured, and good removal of paper dust and conveyance of the paper 3 can be achieved.

Further, in this laser printer 1,
The re-conveying unit 41 is provided, and the first conveying unit 9 is arranged on the upstream side in the conveying direction of the paper 3 with respect to the connection portion of the re-conveying path 53 in the paper feeding conveying path 38, while the second conveying unit 9 is arranged. The section 10 is arranged on the downstream side in the transport direction of the paper 3 with respect to the connecting portion.

As a result, the first paper dust removing roller 9b is
Since the sheet feeding / conveying path 38 is arranged on the upstream side of the connection portion of the reconveying path 53, it contacts only the sheet 3 fed from the sheet feeding mechanism section 7, and the second paper dust removing roller 1
Since 0b is arranged on the downstream side of the connecting portion, it contacts both the sheet 3 fed from the sheet feeding mechanism section 7 and the sheet 3 re-conveyed from the re-conveyance path 53.

Therefore, the first paper dust removing roller 9b removes only a larger amount of paper dust produced by the rubbing between the pad member 13b and the paper feeding mechanism section 7, while the second paper dust removing roller 9b removes the second paper dust. The take-off roller 10b is fed from the paper feed mechanism unit 7, and the first paper dust removing roller 9b has already removed most of the larger amount of paper dust caused by rubbing against the pad member 13b. The powder and the paper dust of the paper 3 re-conveyed from the re-conveyance path 53, not from the paper feed mechanism unit 7 (that is, the re-conveyed paper 3 is in contact with the roller 9g of the first paper dust removing roller 9b). Since the image forming surface to be used is the normal back surface side, there is no paper dust generated on the front surface by rubbing with the pad member 13b, and the entire paper dust is removed by the second paper dust removing roller 10b. Remove only) Runode, the removal of appropriate paper dust corresponding to state of adhesion of paper dust of the sheet 3, can be efficiently achieved.

The laser printer 1 is provided with one first transport section 9 and one second transport section 10 each having a first paper dust removing roller 9b and a second paper dust removing roller 10b. In the invention, a plurality of each may be provided, and the first transport unit 9 or the second transport unit 1 may be provided.
It is also possible to provide a plurality of only any one of 0.

In addition, the first transport unit 9 having the first paper dust removing roller 9b and the second transport unit 9 having the second paper dust removing roller 10b are provided.
Although it is arranged on the upstream side of the conveying section 10, contrary to such arrangement, the second conveying section 1 including the second paper dust removing roller 10b is provided.
0 may be arranged on the upstream side of the first transport unit 9 including the first paper dust removing roller 9b.

In this case, the paper dust on the paper 3 is
The width of the first paper dust removing roller 9b and the first sponge member 9c is preferably formed wider than that described above because the second paper dust removing roller 10b slightly spreads in the width direction of the paper 3. .

As shown in FIG. 1, the feeder section 4 of the laser printer 1 further includes a multi-purpose tray 14 on which sheets 3 of arbitrary size are stacked, and a sheet stacked on the multi-purpose tray 14. A multi-purpose paper feed mechanism unit 15 for feeding 3 and a multi-purpose transport unit 16 are provided.

As shown in FIG. 2, the multi-purpose paper feeding mechanism section 15 includes a multi-purpose paper feeding roller 15a and a multi-purpose separating pad 15b opposed to the multi-purpose paper feeding roller 15a. The multi-purpose separating pad 15b includes a support frame 15c, a multi-purpose pad member 15d, and a spring 15e.

The support frame 15c has a flat plate-shaped one end portion which faces the multi-purpose paper feed roller 15a, and a cross section L which is swingably supported by the main body casing 2.
The character-shaped other end is integrally formed, and a multi-purpose pad member 15d is embedded in one end thereof, and a spring 15e is arranged on the back side thereof.
The multipurpose paper feed roller 15a is biased by 5e so that the multipurpose pad member 15d is pressed.

The multi-purpose pad member 15d has a substantially rectangular plate shape and is made of an elastic member such as urethane rubber.
The width of the multi-purpose separating pad 15b is the width A of the paper 3.
Is formed narrower than. That is, the multi-purpose separating pad 15b is formed to have a width that contacts only the central portion in the width direction of the paper 3 for feeding the paper.

Then, the uppermost sheet 3 stacked on the multi-purpose tray 14 is rotated by the multi-purpose sheet feeding roller 15a so that the multi-purpose sheet feeding roller 15a is rotated.
And the multi-purpose separation pad 15b, and by their cooperation, the sheets are separated and fed one by one.

The multi-purpose sheet feeding section 16 has a multi-purpose sheet feeding mechanism section 15 in the sheet feeding direction above the second sheet feeding section 10 on the front side of the sheet feeding and transporting path 38.
And a multi-purpose paper conveying roller 16a which is arranged on the downstream side of the registration roller 11 and on the upstream side of the registration roller 11, and a multi-purpose paper dust removing roller 16b which is arranged to face the multi-purpose conveying roller 16a.
And the multi-purpose sponge member 16 that is disposed below the multi-purpose paper dust removing roller 16b so as to face each other.
and c.

The multi-purpose conveying roller 16a has a metal roller shaft 16d covered with a rubber roller 16e, and the power is transmitted from a motor (not shown) to the arrow direction (counterclockwise direction in FIG. 1). It is configured to be driven to rotate.

The multi-purpose paper dust removing roller 16b is
It is formed as a member substantially similar to the above-mentioned first paper dust removing roller 9b, and its surface is easily charged, such as a roller made of fluororesin on the metal roller shaft 16f or a roller whose surface is coated with fluorine. Rubber roller 16
g are coated. The multi-purpose paper dust removing roller 16b comes into contact with the contact portion of the multi-purpose pad member 15d on the surface of the multi-purpose separating pad 15b of the paper 3 fed by the multi-purpose paper feeding roller 15 which is in contact with the multi-purpose pad member 15d. As described above, the multi-purpose transport roller 16a that overlaps the multi-purpose separating pad 15b in the transport direction of the sheet 3
Is arranged in the substantially central portion of the roller 16g
Is slightly wider than the width of the multi-purpose pad member 15d.

The multi-purpose paper dust removing roller 16b is driven by the multi-purpose conveying roller 16a in the direction of the arrow, that is, in the contacting portion with the paper 3, it is in the same direction as the conveying direction of the sheet 3 (clockwise in FIG. 1). Direction)) to remove the paper dust on the paper 3 and the multi-purpose conveying roller 16a and the multi-purpose paper dust removing roller 16
The sheet 3 is sandwiched between b and the sheet 3 is conveyed.

The multi-purpose sponge member 16c is a multi-purpose paper dust removing roller 1 such as urethane foam.
6b is made of a material that is easily charged, so that the multi-purpose paper dust removing roller 16b can scrape paper dust below the paper feed path from the multi-purpose paper feed mechanism 15 on the opposite side. The multi-purpose paper dust removing roller 16b is arranged below the dust removing roller 16b so as to be pressed against the multi-purpose paper dust removing roller 16b. The multi-purpose paper dust removing roller 16b scrapes away the paper dust and the multi-purpose paper dust removing roller 16b. The surface of the roller 16g of the multi-purpose paper dust removing roller 16b is frictionally charged by rubbing with.
The width of the multi-purpose paper dust removing roller 16b
It is formed slightly wider than the width of the roller 16g.

The sheets 3 fed from the multi-purpose sheet feeding mechanism section 15 are also separated one by one by the cooperation of the multi-purpose sheet feeding roller 15a and the multi-purpose separating pad 15b as described above. However, a large amount of paper dust is generated by rubbing between the multi-purpose separating pad 15b and the paper.
However, when the paper 3 is conveyed to the multi-purpose conveying unit 16, when the paper 3 is conveyed while being sandwiched between the multi-purpose conveying roller 16a and the multi-purpose paper dust removing roller 16b, the multi-purpose paper dust removing roller 16b moves to the multi-purpose. Since it is formed slightly wider than the width of the separation pad 15b, the multi-purpose pad member 15d is formed on the sheet 3 by the friction between the separation pad 15b and the multi-purpose separation pad 15b.
The paper dust generated with a width substantially equal to the width is scraped off by the roller 16g of the multi-purpose paper dust removing roller 16b and electrostatically adsorbed. Then, the paper dust attached to the roller 16g of the multi-purpose paper dust removing roller 16b is
Multi-purpose paper dust removing roller 16b arrow direction (Fig. 1
Then, it is scraped off by the multi-purpose sponge member 16c.

As a result, the paper dust generated on the sheet 3 by the rubbing against the multi-purpose separating pad 15b and having a width substantially equal to the width of the multi-purpose separating pad 15b is transferred to the multi-purpose conveying section 16 to remove the paper dust. Clearly removed from the surface.

In the laser printer 1, the paper dust scraped off by the first sponge member 9c, the second sponge member 10c, and the multi-purpose sponge member 16c drops by its own weight when it becomes a lump to some extent. However, a drop guide passage 39 for guiding the falling paper dust is formed. That is, the drop guide passage 39 is provided on the front side of the paper feed / conveyance path 38.
The guide plate 6 is formed as a passage extending in the vertical direction.
1, an extension portion 62, a partition plate 63, and the like.

The guide plate 61 is a thin plate-like member which constitutes the front side of the paper feed / conveyance path 38 for guiding the paper 3 from the paper feed mechanism 7 to the image forming unit 5, and guides the paper dust on the back side thereof. Is configured. More specifically, the guide plate 61 includes a first guide plate 61 a that guides the sheet 3 from the second transport unit 10 to the registration rollers 11, and a first guide plate 61 a that guides the sheet 3 from the first transport unit 9 to the second transport unit 10. 2 guide plates 61b.

The first guide plate 61a is used by the registration roller 11
Is formed as a thin plate member extending obliquely from the front of the second conveyance unit 10 to above the second conveyance unit 10. The front side surface guides the conveyance of the sheet 3 from the second conveyance unit 10 to the registration roller 11, and the back side surface thereof. In the above, it is formed so as to guide the paper powder falling from the multi-purpose conveying unit 16 arranged above the first guide plate 61a downward. In addition, an extension portion 62 extending diagonally downward is provided at a lower end portion thereof so as to cover an upper portion of the second transport portion 10.
a is integrally formed.

The second guide plate 61b is formed as a thin plate member that gently extends from below the second transport unit 10 to below the first transport unit 9 so as to curve in a substantially S-shape. , Guiding the conveyance of the sheet 3 from the first conveying section 9 to the second conveying section 10, while at the back side thereof,
In addition to the paper powder falling from the multi-purpose transport unit 16,
The second guide plate 61b is formed so as to guide the paper dust falling from the second transport unit 10 arranged at the upper end of the second guide plate 61b downward. In addition, a thin plate-shaped extending portion 62b extending obliquely downward is provided so as to cover the upper portion of the first transport portion 9 from the middle in the vertical direction.

In addition, at the lower end of the second guide plate 61b,
A receiving plate 61 that is bent and formed in a substantially orthogonal shape toward the front side.
c is integrally formed. This receiving plate 61c is
The multi-purpose transport unit 16, the second transport unit 10, and the first transport unit 9 are arranged above the attachment / detachment path of the paper feed tray 6 in a substantially horizontal direction along the attachment / detachment path, and have upper surfaces thereof.
The receiving surface 65 receives the paper dust that drops after being removed from the paper 3 by.

The partition plates 63 are opposed to each other in the front of the second guide plate 61b with a predetermined space therebetween. The side plates 63c are arranged substantially vertically and vertically, and the side plates 63c.
And a bottom plate 63d that is bent from the lower end toward the front side are integrally formed. Further, at the front end portion of the bottom plate 63d, a paper dust carrying plate 66 and a carrying driving unit 67 which will be described later are provided.
The plate-shaped fixing portion 63a to which is fixed is bent upward in a substantially vertical shape.

Then, in the multi-purpose conveying section 16, the paper dust scraped off by the multi-purpose sponge member 16c is guided to the back side surface of the first guide plate 61a and the extending portion 62a, and the second paper dust removing roller. 10b, and then guided by the back side surface of the second guide plate 61b and the extending portion 62b, the first paper dust removing roller 9b.
, And then to the receiving surface 65.

Further, in the second transport section 10, the paper dust scraped off by the second sponge member 10c is guided to the back side surface of the second guide plate 61b and the extending portion 62b, and the first paper dust removing roller. It falls to the upper side of 9b, and then falls to the receiving surface 65.

The paper dust scraped off by the first sponge member 9c also falls on the receiving surface 65.

The laser printer 1 is removed from the sheet 3 by the multi-purpose carrying section 16, the second carrying section 10 and the first carrying section 9 and the receiving surface 6 by its own weight.
The paper dust storage unit 68 for collectively storing the paper dust dropped on the sheet 5, and the paper as a paper dust transporting unit for transporting the paper dust received by the receiving surface 65 to the paper dust storage unit 68. It is provided with a powder carrying plate 66 and a carrying driving unit 67 for driving the paper powder carrying plate 66.

As shown in FIG. 5, the paper dust storage section 68 is a space below the multi-purpose carrying section 16, the second carrying section 10 and the first carrying section 9 and on both sides of the receiving surface 65 in the width direction. It is formed so that the paper dust received on the receiving surface 65 can be collectively stored.

The paper dust carrying plate 66 is disposed above the attachment / detachment path of the paper feed tray 6 via the receiving surface 65, and as shown in FIG. As shown in FIG. 7, a sweeping plate 70 having a substantially L-shape that is formed so as to project rearward in the orthogonal direction from the center in the width direction of the lower portion of the base portion 69 and extends to the lower portion of the first transporting portion 9 is integrally formed. As shown in FIG. 4, the sweeper plate 70 is formed in a substantially T-shape in a plan view so that the sweeper plate 70 protrudes from the central portion in the width direction of the base portion 69. Then, the base portion 69 of the paper dust carrying plate 66
Is fixed to a rack 74 of a transport driving unit 67 described later with a fixing portion 63a of the partition plate 63 interposed therebetween by a screw 71, and by moving the rack 74, the horizontal direction along the horizontally elongated hole portion 63b of the fixing portion 63a. It is configured to move back and forth. As shown in FIG. 2, the lower end edge of the sweep plate 70 is arranged so as to be separated from the receiving surface 65 by a predetermined gap (about 2 mm), and the lower end edge of the sweep plate 70 reciprocates. The receiving surface 65 is not rubbed during movement.

As shown in FIG. 2, the transport drive unit 67 is above the paper dust transport plate 66 and the paper dust storage unit 68, and the first transport unit 9, the second transport unit 10, and the multi-purpose transport unit. 16 and the partition plate 63 so as to be separated from each other, and the power transmission mechanism 94 (see FIG. 6),
The first bevel gear 72, the compound gear 73, and the rack 74 are provided.

The power transmission mechanism 94 is provided along the side wall of the main body casing 2 and, as shown in FIG. 6, has an input gear 77, a conversion gear portion 78, and an output gear 79.

The input gear 77 is provided at the shaft end portion of the input shaft 80 for transmitting the power that is rotationally driven in one direction from a motor (not shown), and is the first of the conversion gear portions 78 described later.
It is configured to mesh with the conversion gear 81.

The conversion gear portion 78 includes a first conversion gear 81,
The second conversion gear 82, the pendulum member 83, and the third conversion gear 84 are provided.

The first conversion gear 81 includes a first external gear 85 having a larger diameter that meshes with the input gear 77 and a first external gear 85.
And a first internal gear 86 having a smaller diameter and meshing with a second conversion gear 82 described later.

The second conversion gear 82 has outer peripheral teeth that mesh with the first internal gear 86 of the first conversion gear 81, and is located at a position radially outward from the axial center thereof by a predetermined distance along the axial direction. A cylindrical projecting cylinder portion 87 that projects inward is formed, and the projecting cylinder portion 87 is loosely inserted into a long hole portion 88 of the pendulum member 83 described below.

The pendulum member 83 is formed as an elongated substantially fan-shaped plate member, and an arc tooth portion 89 that meshes with a third internal gear 92 of the third conversion gear 84 described later is formed in the arc portion at the lower end thereof. Has been done. Also, this pendulum member 8
The elongated hole portion 88 that is elongated and opened along the central portion in the longitudinal direction is formed in the reference numeral 3, and the support portion 90 serving as a swing fulcrum is provided between the arcuate tooth portion 89 and the elongated hole portion 88. It is provided. The pendulum member 83 is swingably supported with the supporting portion 90 as a fulcrum, and the long hole portion 88 is provided.
The protruding cylinder portion 87 of the second conversion gear is disposed in the state of being loosely inserted.

The third conversion gear 84 is the output gear 7 described later.
A third external gear 91 having a larger diameter that meshes with the gear 9, and a third internal gear 92 having a smaller diameter that is provided inside the third external gear 91 and meshes with the arc tooth portion 89 of the pendulum member 83 are integrated. Be prepared for.

The output gear 79 is a first bevel gear 72 to be described later.
It is provided on one end side of the output shaft 93 that transmits power to the third conversion gear 84, and is configured to transmit the power of the third external gear 91 of the third conversion gear 84 to the first bevel gear 72 described later.

As shown in FIG. 4, the first bevel gear 72 is a compound gear arranged substantially orthogonal to the first bevel gear 72 on the other end side of the output shaft 93 for transmitting the power from the output gear 79. It is provided so as to mesh with a second bevel gear 76 of 73 which will be described later.

As shown in FIG. 2, the compound gear 73 has a pinion gear 7 on its outer periphery that meshes with a rack 74 described later.
5 and the first pinion around the inner shaft center of the pinion gear 75.
The bevel gear 72 and the second bevel gear 76 meshing with the bevel gear 72 are integrally formed, and the pinion gear 75 is arranged so as to be oriented in a substantially horizontal direction.

The rack 74 has rack teeth 74a which mesh with the pinion gear 75 of the composite gear 73 on the surface thereof, and is formed as a rectangular plate member slightly wider than the width of the first paper dust removing roller 9b. This rack 74 has its rack teeth 74a.
Are arranged parallel to the axial direction of the first paper dust removing roller 9b in a state of meshing with the pinion gear 75, and the rotation of the pinion gear 75 causes the back surface of the pinion gear 75 to slidably contact the fixed portion 63a of the partition plate 63. , First paper dust removing roller 9b
It is configured to linearly reciprocate in the horizontal direction along the axial direction.

Then, in the transport drive section 67, as shown in FIG. 6, when the power for rotationally driving in one direction from a motor (not shown) is transmitted to the input gear 77, the input gear 7
Since the first external gear 85 of the first conversion gear 81 that meshes with the first internal gear 8 is rotationally driven, the first internal gear 8 of the first conversion gear 81
The second conversion gear 82 is rotationally driven via 6, and the protruding cylindrical portion 87 moves in the circumferential direction in a circular orbit. As a result, the pendulum member 83 having the projecting cylinder portion 87 inserted into the elongated hole portion 88 is swung to the left and right with the support portion 90 as a fulcrum, and the arc tooth portion 89 reciprocates left and right, whereby the arc tooth Power that is rotationally driven in one direction is converted into power that is driven in a reciprocating direction and transmitted to the third internal gear 92 that meshes with the portion 89. Therefore, when the power is transmitted from the third internal gear 92 to the output gear 79 via the third external gear 91, the output gear 79 is rotationally driven so as to repeat forward and reverse rotations at a predetermined cycle. It

Then, as shown in FIG. 4, this power is
When transmitted to the first bevel gear 72 via the output shaft 93 and further transmitted from the second bevel gear 76 to the rack 74 via the pinion gear 75, the rack 74 is horizontally reciprocally driven at a predetermined cycle. . This allows the rack 74
The paper dust carrying plate 66 fixed to the
As shown in FIG. 5, on the receiving surface 65 along the axial direction of the first paper dust removing roller 9b to both side positions (positions outside both axial ends of the first paper dust removing roller 9b) indicated by imaginary lines. It is reciprocated substantially horizontally. Therefore, the sweep plate 7
0, as will be described later,
The first paper dust removing roller 9b is driven so as to linearly reciprocate in the horizontal direction and sweep to the paper dust storing portion 68 outside the both axial ends thereof.

Further, in the transport drive section 67, when the drive is transmitted from the input gear 77 to the output gear 79,
The speed of the reciprocating movement of the paper dust carrying plate 66 is set to 100 mm / sec or less by deceleration due to the combination of gears.

In the laser printer 1, the transport drive section 67 is disposed above the paper dust transport plate 66 and the paper dust storage section 68 and is defined by the partition plate 63. By the plate 63, the paper dust falling from the multi-purpose transport unit 16, the second transport unit 10, and the first transport unit 9 by its own weight, the paper dust transported by the paper dust transport plate 66, and the paper dust storage unit 68. It is possible to effectively prevent the paper dust stored in (3) from entering the transport drive unit 67. Therefore, it is possible to prevent the malfunction of the transport driving unit 67 due to the invasion of the paper dust and to prevent the transport driving unit 6 from operating.
7 can be ensured, and good paper dust removing operation can be achieved over a long period of time.

Further, in the laser printer 1, the paper dust storage section 6 is configured so that the paper dust is swept by the sweep plate 70 of the paper dust transport plate 66 that reciprocates substantially in the horizontal direction.
8 is transported. Therefore, it is possible to achieve reliable transport with a simple configuration without using a complicated transport mechanism such as an auger member.

Moreover, since the sweeping plate 70 linearly reciprocates along the axial direction of the first paper dust removing roller 9b, it is possible to generate the unswept portion in a minimum space with a simple structure. There is almost no paper dust storage unit 6
8 can be conveyed satisfactorily.

That is, for example, in the case of reciprocating by swinging the one end portion of the sweeping plate 70 about its axis, the swinging locus is increased in order to prevent the unswept portion. Although it is necessary, if the swing locus is made large, it becomes unavoidable that the device becomes large. On the other hand, in order to prevent an increase in size, it is possible to mount a flexible blade member that bends when it comes into contact with another member without increasing the swing locus, but in such a case, However, the structure for mounting the flexible blade member becomes complicated and the number of parts increases.

However, in this way, the sweep plate 70 is
By linearly reciprocating along the axial direction of the paper dust removing roller 9b, the paper dust can be stored in the paper dust storing portion 68 with a simple structure with almost no uncleaned space left behind. It can be transported well.

Further, the paper powder carrying plate 66 is 100 m long.
Since it is set to slowly reciprocate at a speed of m / sec or less, the paper dust on the receiving surface 65 can be conveyed to the paper dust storage unit 68 without being scattered. Therefore, it is possible to more effectively prevent the paper dust from entering the transport drive unit 67, and to achieve a good paper dust removing operation for a long time.

Further, since the sweeping plate 70 reciprocates in the horizontal direction on the receiving surface 65 with a predetermined gap (about 2 mm) from the receiving surface 65, the sweeping plate 70 and the receiving surface 70 It is possible to prevent rubbing against 65 and effectively prevent defective conveyance due to damage to the sweeping plate 70. for that reason,
The durability of the paper dust carrying plate 66 can be improved, and a good paper dust removing operation can be achieved for a long time. In addition, since the paper powder falling on the receiving surface 65 is a certain amount of lumps, even if such a predetermined gap is provided, it can be swept well by the sweep plate 70,
The conveyance of paper dust is not hindered.

Further, in this laser printer 1, the paper dust removed by the multi-purpose transport unit 16, the second transport unit 10, and the first transport unit 9 is transported by the paper dust transport plate 66 in the width direction of the receiving surface 65. Paper dust storage section 6 provided on both sides
Since it is stored in No. 8, it is not necessary to provide a space below the receiving surface 65 for storing paper dust. Therefore, the paper dust carrying plate 66 is arranged above the attachment / detachment path of the paper feed tray 6 so that the paper dust of the paper 3 fed from the paper feed tray 6 can be smoothly removed, and It is possible to secure a smooth attachment / detachment operation of the paper tray 6.

Further, in the laser printer 1, when the power transmission mechanism 94 inputs the power driving in one direction to the input gear 77, the power driving in the one direction is reciprocated by the conversion gear portion 78. Is converted to power to drive in the direction, and then power to drive in the reciprocating direction,
Since the output gear 79 outputs the paper dust carrying plate 66, the power for driving in one direction can be converted into the power for driving in the reciprocating direction to move the paper dust carrying plate 66 back and forth with a simple configuration. it can.

Further, in this laser printer 1, the multi-purpose carrying section 16, the second carrying section 10, and the first carrying section 9 are all arranged vertically in front of the paper feed carrying path 38, and these multi Purpose transport unit 1
The respective paper powders removed by 6, the second transport unit 10 and the first transport unit 9 are guided by dropping in the drop guide passage 39 by their own weight, and are collected on the receiving unit 65 as they are, and thereafter, By the sweeping plate 70, the paper dust storage portion 68
It is stored collectively in. Therefore, the paper dust removed for each of the multi-purpose transport unit 16, the second transport unit 10, and the first transport unit 9 is guided and transported by a simple configuration, and is collectively stored in the paper dust storage unit 68. You can As a result, it is not necessary to store the multi-purpose transport unit 16, the second transport unit 10, and the first transport unit 9, and the device configuration can be simplified, the number of parts can be reduced, and the device can be downsized.

Further, in this laser printer 1, since the drop guide passage 39 is formed by utilizing the back side surface of the guide plate 61 of the paper feed / conveyance path 38, the device construction is further simplified and the number of parts is further increased. Can be reduced and the device can be downsized.

Further, in the laser printer 1, the first guide plate 61a has the extending portion 62 that covers the upper side of the second conveying portion 10.
Since the second guide plate 61b also includes the extending portion 62b that covers the upper portion of the first transport portion 9,
Even if the paper dust removed by the multi-purpose transport unit 16 arranged above the transport unit 10 falls, the extending portion 62a prevents the paper dust from falling on the second transport unit 10. Further, even if the paper dust removed by the multi-purpose conveying unit 16 and the second conveying unit 10 falls onto the first conveying unit 9 arranged below the extending unit 62b, It is possible to prevent the paper dust from falling on the first transport unit 9.
Therefore, the good paper dust removing operation of the first transport unit 9 and the second transport unit 10 can be ensured for a long period of time.

Further, in the laser printer 1, the first paper dust removing roller 9b in the first transport portion 9 first comes into contact with the paper 3 along with its rotation to remove the paper dust on the paper 3. Then, the paper dust adhering to the first paper dust removing roller 9b is scraped off by the first sponge member 9c on the side opposite to the paper feeding and conveying path 38 with respect to the first paper dust removing roller 9b. Also in the second transport unit 10,
The second paper dust removing roller 10b comes into contact with the paper 3 as it rotates to remove the paper dust on the paper 3 and then
The paper dust adhering to the paper dust removing roller 10b is scraped off by the second sponge member 10c on the opposite side of the paper feeding / transporting path 38 with respect to the second paper dust removing roller 10b. Then, the first sponge member 9c and the second sponge member 10
Since the paper dust scraped by c stays below the opposite side of the paper feed / conveyance path 38 and falls into the drop guide passage 39 by its own weight when it becomes a certain amount of lumps,
While effectively preventing the scraped paper dust from entering the paper feed / transport path 38, the paper dust removed by the first transport unit 9 and the second transport unit 10 is collectively collected in the paper dust storage unit 68. It can be stored.

Also in the multi-purpose conveying section 16, the multi-purpose paper dust removing roller 16b is brought into contact with the paper 3 to remove the paper dust on the paper 3 along with its rotation, and then the multi paper is removed. The paper dust adhering to the paper dust removing roller 16b is scraped off by the multi-purpose sponge member 16c on the opposite side of the multi-purpose paper dust removing roller 16b from the paper feed path from the multi-purpose paper feed mechanism unit 15. Then, the paper dust scraped off by the multi-purpose sponge member 16c falls from the inside of the drop guide passage 39 due to its own weight, and thus the scraped paper dust enters the paper feeding path from the multi-purpose paper feeding mechanism unit 15. The paper dust removed by the multi-purpose carrying unit 16 can be collectively stored in the paper dust storage unit 68 while effectively preventing the intrusion.

The laser printer 1 is configured as an electrophotographic laser printer that develops an electrostatic latent image to form a visible image and transfers the visible image onto the paper 3. If there is paper dust, it is particularly necessary to remove the paper dust on the paper 3 because the paper dust mixes into the image forming unit 5 at the time of transfer. Since the first transport unit 9, the second transport unit 10, and the multi-purpose transport unit 16 can efficiently remove the paper dust on the paper 3, it is possible to reliably achieve good image formation by the electrophotographic method. it can.

Further, in the laser printer 1, as described above, the developing roller 27 collects the residual toner remaining on the surface of the photosensitive drum 23 after the transfer by the cleanerless development. When the paper dust from the toner adheres to the surface of the photosensitive drum 23, the paper dust is collected by the developing roller 27 together with the residual toner,
A problem occurs that the toner mixes in the developing cartridge 24 and directly affects the image quality, but according to the above configuration, the first transport unit 9, the second transport unit 10, and the multi-purpose transport unit 16 cause the paper Since the paper dust on No. 3 can be removed efficiently, it is possible to reliably achieve good image formation by simply collecting the residual toner by cleanerless development.

In the above description, the paper dust carrying plate 66 is used as the paper dust carrying means to carry the paper dust on the receiving surface 65. However, for example, an auger member having spiral blades is used. Alternatively, the paper dust on the receiving surface 65 may be conveyed.

More specifically, as shown in FIG. 7, the receiving surface 65 is formed in a curved concave shape capable of receiving the substantially cylindrical auger member 102, and the auger member 102 is disposed on the receiving surface 65. do it.

The auger member 102 includes a shaft member 105 and a shaft member 1 as shown in FIG.
A first spiral portion 106 and a second spiral portion 107 that are formed in a spiral shape around 05 are provided. Also, at one end of the shaft member 105,
An auger drive gear 108 to which power from a motor (not shown) is input is provided to drive the auger member to rotate.

The first spiral portion 106 is formed in a substantially half portion of the shaft member 105 in the axial direction. The rotation of the shaft member 105 causes the paper dust to flow in one direction in the axial direction of the first paper dust removing roller 9b. It is formed so that it can be conveyed in the (arrow X direction). Further, the second spiral portion 107 is the first spiral portion of the shaft member 105.
It is formed in a substantially half portion in the axial direction on the opposite side where the spiral member 106 is formed, and the rotation of the shaft member 105 causes the paper dust to be directed to the other side in the axial direction of the first paper dust removing roller 9b (the direction of the arrow Y). ) Is configured to be transported to.

As a result, the paper dust received on the receiving surface 65 is driven by the rotation of the auger member 102 by the first spiral member 106 and the second spiral member 107, so that both ends of the first paper dust removing roller 9b in the axial direction. Department (Arrow X
And in the arrow Y direction) and is stored in the paper dust storage unit 68.

[0155]

As described above, according to the first aspect of the present invention, the respective paper dusts removed by the plurality of paper dust removing means are collectively stored in the paper dust storing section. Since it is not necessary to store each paper dust removing means, the device configuration can be simplified, the number of parts can be reduced, and the device can be downsized.

According to the second aspect of the invention, the paper dust removed by each paper dust removing means can be collectively stored in the paper dust storing section with a simple structure.

According to the third aspect of the present invention, the paper dust removed by each paper dust removing means can be guided by a simple structure and stored together in the paper dust storage section.

According to the invention described in claim 4, the paper dust removed by each paper dust removing means can be conveyed and stored in a lump with a simple configuration, and the apparatus configuration can be further improved. It is possible to simplify, reduce the number of parts, and downsize the device.

According to the fifth aspect of the invention, since the drop guide passage is formed by utilizing the back surface of the guide plate of the supply / conveyance path, the device structure is further simplified and the number of parts is further reduced. And the size of the device can be reduced.

According to the sixth aspect of the invention, it is possible to ensure a good paper dust removing operation of each paper dust removing means arranged below for a long period of time.

According to the seventh aspect of the invention, the paper dust removing means can achieve good removal of paper dust over a long period of time.

According to the eighth aspect of the present invention, the paper dust removed by each paper dust removing means is effectively prevented from entering the supply transport path, and the paper dust is stored all together. You can

According to the invention described in claim 9, the paper dust removed by each paper dust removing means and falling by its own weight,
It can be collected as it is in one place, and can be collectively stored with a simpler configuration.

According to the tenth aspect of the present invention, it is possible to efficiently achieve appropriate removal of paper powder according to the state of attachment of paper powder.

According to the eleventh aspect of the present invention, since the paper dust on the recording medium can be efficiently removed, good image formation can be reliably achieved by the electrophotographic method.

According to the twelfth aspect of the present invention, by the cleanerless development, good image formation can be reliably achieved while easily collecting the developer.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part showing an embodiment of a laser printer as an image forming apparatus of the present invention.

FIG. 2 is an enlarged side sectional view of an essential part showing a sheet feeding / conveying path of a sheet of the laser printer shown in FIG.

FIG. 3 (a) shows the laser printer shown in FIG.
Is a plan view of an essential part of the sheet, (b) is a cross-sectional view of the second paper dust removing roller, (c) is a cross-sectional view of the first paper dust removing roller,
(D) shows the top view of a pad member.

4 is a plan cross-sectional view of a main part of a paper dust conveying section and a conveyance driving section in the laser printer shown in FIG.

FIG. 5 is a front view of a paper dust transport unit of the laser printer shown in FIG.

6A and 6B are a power transmission mechanism of the laser printer shown in FIG. 1, wherein FIG. 6A is a side sectional view of the power transmission mechanism, and FIG.
The front view of a power transmission mechanism is shown.

7 is an enlarged side cross-sectional view of a main part of another embodiment (which conveys paper dust using an auger member) of the paper feed / conveyance path of the laser printer shown in FIG. 1. FIG.

FIG. 8 is a plan view of a main part of a paper dust conveying section of the laser printer shown in FIG.

[Explanation of symbols]

1 laser printer 3 sheets 5 Image forming section 7 Paper feed mechanism 9 First transport section 9b First paper dust removing roller 9c First sponge member 10 Second transport section 10b Second paper dust removing roller 10c Second sponge member 12 paper feed rollers 13 Separation Pad 23 Photosensitive drum 27 developing roller 38 Paper feed transport path 39 Fall guide passage 41 Re-conveying unit 53 Re-transportation route 61 Information board 61a First guide plate 61b Second guide plate 62a extension part 62b extension part 66 Paper powder transport plate 68 Paper dust storage

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H072 AA02 AB07 BA13 CA01 CA02                       CB09                 2H134 GA08 GB05 HA01 KG10 KH03                       KH09                 3F101 AB01 AB07 AB19 LA02 LA07                       LB03

Claims (12)

[Claims] 1. A paper dust removing means for removing paper dust of a recording medium supplied to an image forming means, and a paper dust storing section for storing the paper dust removed by the paper dust removing means. In the image forming apparatus, the paper dust removing unit is provided in plural in a supply / conveyance path for supplying a recording medium to the image forming unit, and the paper dust storage unit is provided by the plurality of paper dust removing units. An image forming apparatus, characterized in that the removed paper dusts are collectively stored. 2. The paper dust storage section is provided below the paper dust removing means, and stores the paper dust dropped by its own weight after being removed by the paper dust removing means. The image forming apparatus according to claim 1. 3. The image forming apparatus according to claim 2, further comprising: a drop guide passage for guiding the paper dust that is dropped by its own weight after being removed by each of the paper dust removing means. 4. A paper dust carrying means for carrying the paper dust removed by each of said paper dust removing means toward said paper dust storing portion, wherein said paper dust carrying means is provided. The image forming apparatus according to any one of 1. 5. The supply / transport path is provided with a guide plate for guiding a recording medium, and the drop guide passage is formed by a back side of the guide plate. Alternatively, the image forming apparatus according to item 4. 6. The image forming apparatus according to claim 5, wherein the guide plate includes an extension portion that covers at least an upper portion of the paper dust removing unit arranged below. 7. Each of the paper dust removing means comes into contact with a recording medium to remove the paper dust, and a paper dust removing member that faces the paper dust removing member and is attached to the paper dust removing member. The image forming apparatus according to any one of claims 1 to 6, further comprising a scraping member for scraping off. 8. In each of the paper dust removing means, the paper dust removing member is configured to be movable in the same direction as the recording medium transport direction in a portion facing the supply transport path, and the scraping member. The image forming apparatus according to claim 7, wherein the paper dust removing member is configured to scrape away the paper dust below the paper feeding member on the opposite side of the supply transport path. 9. The paper dust removing device according to claim 1, wherein the plurality of paper dust removing units are arranged in a vertical direction on one side of the supply transport path to which a recording medium is supplied. The image forming apparatus according to item 1. 10. A supply unit that includes a separation pad and a supply roller that supplies a recording medium to the supply conveyance path, and a recording medium having an image formed on one surface thereof by the image forming unit is turned upside down. And a re-conveyance path for conveying the recording medium again toward the image forming unit, wherein a downstream end of the re-conveyance path is connected in the middle of the supply conveyance path, The first paper dust removing unit is provided on the upstream side in the transport direction of the recording medium with respect to the connection portion of the re-transport path in, and on the downstream side in the transport direction of the recording medium from the connection portion, A paper dust removing means is provided, and the paper dust removing member of the first paper dust removing means is at least wider than the separation pad width of the separation pad in the direction orthogonal to the recording medium conveyance direction. In addition to having a width, the paper dust removing member of the second paper dust removing means has a width that is at least wider than the recording medium width in the direction orthogonal to the recording medium conveyance direction. The image forming apparatus according to any one of 7 to 9. 11. The image forming means is constituted by an electrophotographic system, which forms an image by transferring a visible image formed by developing an electrostatic latent image onto a recording medium. 11. Characteristic features 1 to 10.
The image forming apparatus according to any one of 1. 12. The image forming means includes a photoconductor on which an electrostatic latent image is formed, and a developing means for supplying a developer, and a nonmagnetic one-component developer is used as the developer. The
The image forming apparatus according to claim 11, wherein cleanerless development is performed in which the developer remaining on the photosensitive member after transfer is collected by a developing unit.