JPH0489733A - Electronic photographing device - Google Patents

Abstract

PURPOSE:To improve printing quality by removing the paper powder clung to a transfer paper by a paper powder removing device before carrying the transfer paper to a transcribing device. CONSTITUTION:Transfer papers P in a cassette 11 are fed one by one by a feed roller 12, and carried to transcribing device 8 by a carrying roller pair 21a, 21b for transfer. The carrying roller 21b is frictionally electrified by a paper powder removing member 32, and the paper powder of the transfer papers P is attracted by the roller 21b and removed by the removing member 32. Thus, the paper powder of the transfer paper P carried to the transcribing device 8 is removed to prevent the generation of black lines on printed characters and after-image development, and the quality is largely improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to electrophotographic devices such as copying machines, facsimile machines, and laser printers.

[Conventional technology] FIG. 3 shows a schematic configuration of a conventional electrophotographic apparatus.

In the figure, 1 is the main body of the device. The apparatus main body 1 includes a photosensitive drum 4 as an image carrier. Charging device 5, developing device 7
．． Transfer device8. Cleaning device 9, paper feed unit (cassette 11, paper feed roller 12) and conveyance means (conveyance roller 2)
1a, 21b, a kite board 25), etc. are built-in.

Here, when a printing operation is performed, the photosensitive drum 4 is rotated in the direction of the arrow and its peripheral surface is uniformly charged by the charging device 5. On the uniformly charged photosensitive drum surface,
A laser beam 6 is irradiated from an optical system (not shown) based on print data to form an electrostatic latent image. This electrostatic latent image is developed by a developing device 7 into a toner image. Then, in the transfer device 7, the toner image on the photosensitive drum 4 is transferred onto a transfer paper P that is taken out from the cassette 11 by a paper feed roller 12 and transported by transport rollers 21a, 21b, etc. The toner image transferred onto the transfer paper P is fixed in a fixing device (not shown).

Note that the toner remaining on the photosensitive drum 4 after the transfer is completed is removed by the blade 9a of the cleaning device 9.

[Problem to be Solved by the Invention 1] Incidentally, in the electrophotographic apparatus described above, the transfer paper P often has paper dust attached to its edges and surface. Therefore, when the paper dust on the transfer paper P comes into contact with the photosensitive drum 4 during the transfer wave W8, it may adhere to the photosensitive drum 4. When it enters the contact area,
In printing, black streaks, afterimages, etc. occur, resulting in an inconvenience in which printing quality deteriorates.

Further, if paper dust accumulates on the conveyance path of the transfer paper P, the paper dust may clog gears for driving the conveyance roller 21a and the like, causing damage.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a paper dust removal device for an electrophotographic apparatus that can remove paper dust from transfer paper conveyed to a transfer device.

[Means to solve the problem] The present invention relates to an image carrier capable of forming a toner image.

a transfer device disposed around the image carrier, an electronic device that conveys the transfer paper to the transfer device, and transfers the toner image formed on the image carrier onto the transfer paper in the transfer device. The photographic apparatus is characterized in that it includes a paper dust removal device that removes paper dust attached to the transfer paper before the transfer paper is conveyed to the transfer device.

[Function] In the present invention, the transfer paper is removed by the paper dust removal device before being conveyed to the transfer device. This prevents paper dust attached to the transfer paper from being brought into the transfer device, and prevents paper dust from adhering to the image carrier during the transfer process.

This prevents paper dust from adhering to the image carrier.
The occurrence of black lines and afterimage development on printing is prevented, and printing quality is greatly improved. In addition, paper powder will not clog the gears of the conveyance rollers and cause damage.

[Example] An embodiment of the present invention will be described based on the drawings.

As shown in FIG. 1, the electrophotographic apparatus according to this embodiment has process kits I to 2. Transfer device8. Paper feed section (cassette 11
, paper feed roller 12) and conveyance means (conveyance roller 21a)
, 21b, guide plate 25), etc., and is also provided with a paper dust removing device 31, which removes paper dust adhering to the transfer paper P before starting the transfer process.

Components that are the same as those shown in FIG. 3 are given the same reference numerals, and their explanations will be omitted or simplified.

Here, the process kit 2 includes a photosensitive drum 4. A photosensitive drum unit including a charging device 5, a cleaning device 9, etc., and a developing device 7 are housed in a process kit housing case 3.

Further, the paper dust removing device 31 is a means for removing paper dust attached to the transfer paper P before the transfer paper P is conveyed to the transfer device. Specifically, the paper dust removing device 31 includes a rotating member that comes into contact with the transfer paper P, and a paper dust removing member 32 that frictionally charges this rotating member and removes paper dust that has been attracted to the rotating member. It is configured.

In this embodiment, the rotating member is formed using a conveying roller 21b in order to simplify the structure and reduce costs. The conveying roller 21b contacts the edge portion and surface of the transfer paper P to feed and urge the transfer paper P, and its peripheral surface is formed of a high friction material such as rubber.

On the other hand, the paper dust removing member 32 is attached to the process kit housing case 3 for convenient attachment, replacement, etc.

The mounting position of this paper dust removing member 32 is selected so that the paper dust removing member 32 contacts the rotating member (transport roller 21b) with a predetermined contact pressure when the process kit storage case 3 is attached to the apparatus main body 1. has been done. Further, the paper dust removing member 32 is made of polyester film. The thickness of the polyester film is 50 mm depending on the usage.
It is selected from ~250 μm. In this example, the thickness of the polyester film is 100 μm.

Next, the effect will be explained.

The transfer paper P taken out from the cassette 11 by the paper feed roller 12 is transported toward the transfer device 8 by transport rollers 21a, 21b, etc.

At this time, paper dust attached to the transfer paper P is removed by a paper dust removal device 31 before entering the transfer device.

That is, the conveyance roller 21 that constitutes the paper dust removal device 31
b is frictionally charged by the paper dust removal member 32 or the like, so the paper dust of the transfer paper P is attracted to the transport roller 21b when it is nipped and transported by the transport rollers 21a and 21b. Then, the paper dust attracted to the conveyance roller 21b is removed by the paper dust removal member 32.

This prevents paper dust attached to the transfer paper P from being carried into the transfer process, and prevents paper dust from adhering to the photosensitive drum 4. Therefore, the occurrence of ring streaks, afterimage development, etc. on printing is prevented.

Here, Table 1 shows the results of testing the difference in printing quality depending on the presence or absence of a paper dust removal device.

○: No black streaks, afterimages, etc.

Δ: Slight black lines, afterimages, etc. occur.

×: Significant occurrence of ring streaks, afterimages, etc.

Here, as shown in Table 1, in the conventional electrophotographic apparatus not equipped with the paper dust removing device 31, the number of printed sheets is 600.
If the number of sheets exceeds 0, ring streaks, afterimages, etc. will occur.
In this electrophotographic apparatus equipped with the paper dust removing device 31,
Even if the number of printed sheets is 9,000, ring streaks, afterimages, etc. do not occur.

According to this embodiment, the transfer paper P is transferred to the transfer device 8.
Since the structure is equipped with a paper dust removal device 31 that removes paper dust that adheres to the transfer paper P before it is conveyed to the transfer device 8, it is possible to remove paper dust from the transfer paper P that is conveyed to the transfer device 8. can. This prevents the occurrence of ring streaks, afterimage development, etc. on the print, and greatly improves the print quality. Moreover, since paper dust does not accumulate on the conveyance path, there is no possibility that paper dust will clog gears for driving the conveyance roller 21a and the like and cause damage.

Furthermore, when the process kit storage case 3 is attached to the main body 1 of the apparatus, the paper dust removing member 32 is removed from the rotating member (transport roller 21
Since it is configured to contact b) with a predetermined contact pressure, the paper dust removing device 31 can be easily set and is convenient for handling.

Further, the rotating member of the paper dust removing device 31 is moved to the conveying roller 21.
Since the structure is formed using B, it is possible to reduce the cost without complicating the structure.

In the above embodiment, the paper dust removing member 32 was formed from a polyester film, but what would be possible if the rotating member (transport roller 21b) could be frictionally charged and the paper dust adsorbed to the rotating member could be removed? It may be formed from any material. For example, the thickness of the paper dust removing member 32 is 3 to 5.
It may be formed from a felt member of about mm.

Further, as a conveyance roller, a pair of conveyance rollers 21a, 2
1b is selected, but a plurality of sets of conveyance rollers may be provided depending on the length of the conveyance path.

[Effects of the Invention] According to the present invention, the structure includes a paper dust removal device that removes paper dust attached to the transfer paper before the transfer paper is conveyed to the transfer device, so that the paper dust removed from the transfer paper is removed. It is possible to remove paper dust from transfer paper.

This prevents paper dust from adhering to the image bearing member, prevents ring streaks on prints, afterimage development, etc., and greatly improves print quality. In addition, paper powder does not become clogged with gears for driving conveyance rollers and the like, causing damage.

[Brief explanation of drawings]

1 and 2 are diagrams showing one embodiment of the present invention, in which FIG. 1 is a diagram showing the overall configuration, and FIG. 2 is a diagram showing main parts. Third
The figure is a diagram showing a schematic configuration of a conventional electrophotographic apparatus. 4... Photosensitive drum (image carrier), 8... Transfer device, 31... Paper dust removal device.

Claims (1)

[Claims] (1) An image carrier capable of forming a toner image and a transfer device disposed around the image carrier, a transfer paper is conveyed to the transfer device, and the transfer device transfers the toner image onto the transfer paper. An electrophotographic apparatus for transferring a toner image formed on an image carrier, comprising a paper dust removal device for removing paper dust attached to the transfer paper before the transfer paper is conveyed to the transfer device. An electrophotographic device featuring: