JP2004317962A - Cleaning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning system whose cleaning blade is disposed on an upper part of a photoreceptor drum and that includes the blade, a fur brush, a plate for scraping toner from the brush, and a recovered toner conveyance member, wherein the fur brush is prevented from being soiled again with scraped toner and the conveyance efficiency of the recovered toner conveyance member is improved. <P>SOLUTION: A toner scraping auxiliary sheet or film 25 is disposed so as to be in contact with the fur brush 10 while a space between a toner recovering spiral 15 and the fur blush 10 is partitioned. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cleaning device used in an electrophotographic image forming apparatus such as a copying machine, a facsimile, and a printer.
[0002]
[Prior art]
2. Description of the Related Art In an electrophotographic image forming apparatus represented by a copying machine, an image carrier (photoconductor) is uniformly charged to a predetermined polarity in a main direction, and is image-exposed by light irradiation based on predetermined image information. An electrostatic latent image is formed, and the electrostatic latent image is developed by a developing method such as a magnetic brush developing method to form a toner image on the surface of the image carrier. The toner image thus formed on the surface of the image carrier is transferred to transfer paper using a transfer roller or a corona charger for transfer using electrostatic force, and the transfer paper on which the toner image has been transferred is fixed. The toner image is introduced into the apparatus, and the toner image is fixed on the surface of the transfer paper by heat and pressure to form an image.
On the other hand, after the transfer is completed, the toner remaining on the surface of the image carrier is cleaned by the cleaning device, and further, if necessary, static elimination is performed, whereby one cycle of the image forming process is completed, and the next image forming is performed. Is
[0003]
As a cleaning device used in the above-described image forming apparatus, there is known a cleaning device in which a fur brush is provided in a cleaning housing in addition to a cleaning blade and a recovery spiral. That is, cleaning is performed by scraping off residual toner and paper dust by a cleaning blade pressed against the surface of the image carrier, and the recovered toner and the like are transported to a predetermined disposal area by a recovery spiral. A fur brush is disposed upstream of the blade with respect to the direction of movement of the photoreceptor, and prior to scraping by the blade, the toner or the like adhering to the surface of the image carrier is released by the fur brush, and the image is carried. By floating from the body surface, toner and the like are prevented from slipping through between the blade and the surface of the image carrier, and the scraping effect of the blade is enhanced.
[0004]
In recent years, in order to save resources, images are often formed using inferior paper such as recycled paper. Therefore, a cleaning device provided with a fur brush having a high paper dust removal property has been used.
[0005]
By the way, in a cleaning device provided with a fur brush as described above, a toner scraping plate is often provided in contact with the fur brush (for example, see Patent Document 1).
[Patent Document 1]
JP-A-6-102801
[Problems to be solved by the invention]
That is, in Patent Document 1, a toner accumulation preventing plate (corresponding to a toner scraping plate) is provided in contact with the fur brush, but such a scraping plate must be provided along the cleaning blade. There is. For example, in a compact and small image forming apparatus, a cleaning blade is disposed above a photosensitive drum serving as an image carrier from the viewpoint of saving space. In this case, the cleaning blade is in contact with a fur brush. The scraping plate is provided substantially parallel to the cleaning blade in order to avoid an increase in the size of the cleaning device, and has a structure in which a spiral for transporting the collected toner is provided above the scraping plate.
[0007]
In such a case, there is a problem that the collected toner scraped off from the fur brush by the scraping plate is sprinkled again on the fur brush and adheres to the fur brush. Further, since a space is formed below a member (for example, a spiral) for transporting the collected toner, there is a problem that the transportation efficiency is low.
[0008]
Accordingly, an object of the present invention is to provide a cleaning device in which a cleaning blade is disposed above a photosensitive drum and includes a fur brush, a toner scraping plate from the brush, and a collected toner conveying member together with the blade. It is an object of the present invention to provide a cleaning device in which re-contamination of a fur brush by generated toner is prevented, and the transport efficiency of a collected toner transport member is improved.
Still another object of the present invention is to provide a cleaning device which can be effectively applied to a compact image forming apparatus.
[0009]
[Means for Solving the Problems]
According to the present invention, in a cleaning device for removing a toner remaining on the photosensitive drum after transferring a toner image formed on the photosensitive drum,
A cleaning blade that is in contact with the drum at a position above a horizontal line passing through the center of the photoconductor drum, and that is disposed upstream of the cleaning blade with respect to the rotation direction of the photoconductor drum, and is in contact with the photoconductor drum A fur brush provided so as to rotate in the same direction at the contact nip portion with the drum, a scraping plate for scraping off the toner attached to the fur brush, and toner collected by the cleaning blade. And a conveying member for conveying,
The scraping plate extends along the cleaning blade at a distance from the cleaning blade, and a tip of the scraping plate is in contact with the fur brush,
The transport member is arranged on the upper surface of the scraping plate,
A cleaning device is provided, wherein an auxiliary sheet or film for scraping off toner is arranged so as to contact the fur brush so as to partition a space between the transport member and the fur brush. You.
[0010]
In the present invention, since the auxiliary sheet or film for scraping off the toner is provided so as to partition the space between the conveyance member and the fur brush, the sheet or film is used to scrape off the sheet by the scraping plate. Re-contamination of the fur brush by the toner is prevented. Further, since the sheet or the film functions as a wall for the conveying member of the collected toner, the conveying efficiency of the conveying member can be improved.
[0011]
In the present invention, the auxiliary sheet or the film is in contact with the fur brush so that only one surface thereof is in contact with the fur brush so that the fur brush does not deform or fall down. This is suitable for assisting in scraping off the toner attached to the brush.
[0012]
Further, it is more preferable that the auxiliary sheet or film is formed of a flexible resin material in order to prevent deformation of the fur brush.
[0013]
Further, it is preferable that an opening is formed in the scraping plate. That is, the collected toner stays between the cleaning blade and the scraping plate and accumulates. As a result, the collected toner may overflow and recontaminate the surface of the photosensitive drum. However, by forming an opening in the scraping plate, retention and accumulation of the collected toner can be effectively avoided. Further, by disposing such a scraping plate between the cleaning blade and the conveying member, the toner scraped from the photosensitive drum by the cleaning blade or the toner scraped from the fur brush by the scraping plate can be used. Can be promptly supplied to the conveying member.
[0014]
Further, in the present invention, the cleaning blade may be arranged such that an angle θ between a horizontal line and a straight line connecting a contact point with the photosensitive drum and the center of the photosensitive drum is in a range of 45 to 135 degrees. The photosensitive drum is preferable from the viewpoint of saving space in a small-sized image forming apparatus having a small diameter.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1 showing the structure of the cleaning device of the present invention, the cleaning device indicated by 1 as a whole is arranged so as to face the photosensitive drum 2 rotating in the direction of the arrow in the figure.
[0016]
The cleaning device 1 is unitized integrally with a main charger (for example, a corona charger) indicated by 3, and the cleaning device 1 is located downstream of the main charger 3 with respect to the rotation direction of the photosensitive drum 2. Located on the side.
[0017]
Although not shown in FIG. 1, an optical system for performing image exposure, a developing device, and a transfer device are further provided around the photosensitive drum 2 with respect to the cleaning device 1. It is arranged on the downstream side in the rotation direction.
[0018]
That is, the surface of the photosensitive drum 2 is positively or negatively charged by the main charger 3, and then the optical system irradiates light based on predetermined image information to form an electrostatic latent image on the surface of the photosensitive drum 2. It is formed. The electrostatic latent image is developed by a developing device, a toner image is formed on the surface of the photosensitive drum 2, and further the toner image is transferred onto transfer paper supplied between the transfer device and the photosensitive drum 2. The image is formed by introducing the transfer paper into a fixing device (not shown) and fixing the toner image on the surface of the transfer paper. Further, as described above, the surface of the photoreceptor drum 2 after the transfer of the toner image is cleaned by the cleaning device 1 to remove the toner remaining on the surface, and then the charge is removed, and the image forming process is performed. After the cycle is completed, the next image forming cycle is similarly executed.
[0019]
In the present invention, the cleaning device 1 includes a fur brush 10 and a cleaning blade 11 in a cleaning housing 5, and the fur brush 10 is located upstream of the cleaning blade 11 with respect to the rotation direction of the photosensitive drum 2. Are located in
[0020]
The cleaning blade 11 is made of, for example, an elastic material such as polyurethane rubber, and is mounted on a holder 13 mounted in the housing 5. The tip of the blade 11 is pressed against the surface of the photosensitive drum 2.
[0021]
The fur brush 10 is provided such that the brush tip is in contact with the surface of the photoconductor drum 2, and is configured to rotate in the same direction as the photoconductor drum 2 at the nip portion. That is, foreign matter such as toner or paper dust remaining on the surface of the photosensitive drum 2 after the transfer of the toner image is first released by the fur brush 10 and floats from the surface of the photosensitive drum 2. Then, the cleaning blade 11 is surely scraped off by the cleaning blade 11 and collected in the housing 5.
[0022]
The brush material of the fur brush 10 is not particularly limited, and may be formed of a conductive material or may be non-conductive. Further, the diameter and density of the brush material are appropriately set according to the material of the brush material to be used so that the brush material has appropriate flexibility and can effectively sweep the toner from the photosensitive drum 1. Generally, it is preferable to have a density of about 15,000 to 100,000 lines / inch ² .
[0023]
Further, the fur brush 10 is provided with a scraping plate 14 so as to be in contact with the brush, and the toner and paper powder attached to the fur brush 10 are scraped off by the scraping plate 14. ing.
[0024]
In addition, a recovery spiral 15 is provided in the cleaning housing 5, and the toner and paper powder recovered in the housing 5 are filled in the toner waste container and discarded by the spiral 15.
[0025]
As is clear from FIG. 1, a sealing member 20 made of a resin film or the like is attached to the lower end of the opening of the cleaning housing 5, and a gap between the surface of the photosensitive drum 2 and the cleaning housing 5 is formed by the sealing member. It is closed by the member 20. Thus, the toner collected in the cleaning housing 5 does not scatter outside the housing 5.
[0026]
In the cleaning device 1 described above, the contact point X between the tip of the cleaning blade 11 and the drum 2 is located above a horizontal line passing through the center of the photosensitive drum 1. Particularly preferably, as shown in schematic view of a main portion of FIG. 2, the contact point X and the horizontal line L ² and the angle formed passing through the center of the straight line L ¹ and the drum 1 connecting the drum center θ is 45 to Preferably, the angle is 135 degrees. That is, in a small-sized image forming apparatus in which a small-diameter photosensitive drum 1 having a diameter of, for example, 40 mm or less is used, setting the blade 11 to the above-described position can be performed by changing the position of the sheet feeding cassette or the sheet. This is because it is most preferable to save the space by arranging the transport paths without waste.
[0027]
Further, in connection with the arrangement of the blade 11 at the upper position as described above, the scraping plate 14 in contact with the fur brush 10 is attached to the holder 13 similarly to the blade 11, and And extends substantially parallel above the blade. Further, a recovery spiral 15 is disposed above the scraping plate 14, and as a result, the scraping plate 14 is disposed between the blade 11 and the recovery spiral 15. This is because, when the blade 11 is arranged above, such an arrangement can save unnecessary space and make the cleaning device 1 itself most compact.
[0028]
In the present invention, it is important that an auxiliary sheet or film 25 for scraping off toner is arranged so as to contact the fur brush 10 so as to partition the space between the recovery spiral 15 and the fur brush 10. It is. That is, the auxiliary sheet or film 25 supplements the toner scraping action of the scraping plate 14, reliably prevents the toner from sticking to the fur brush 10, and furthermore, the gap between the wall of the housing 5 and the fur brush 10. Has the function of preventing the accumulation of the toner and preventing the brush 10 from increasing the torque.
[0029]
Further, it is important that the fur brush 10 is protected from the toner scraped off by the scraping plate 14 by providing the auxiliary sheet or film 25 at such a position. Recontamination can be effectively prevented. Further, since the sheet or film 25 is located below the side surface of the collection spiral 15, the sheet or film 25 functions as a wall for the spiral 15, and the conveyance efficiency of the collection spiral 15 can be increased.
[0030]
In the present invention, the auxiliary sheet or film 25 is in contact with the fur brush 10 shallowly so that only one surface thereof contacts the fur brush 10, as shown in FIG. Specifically, it is preferable that the intrusion penetrates into the rotation circle of the fur brush 10 by about 1 to 2 mm. This is because if the sheet or film 25 is deeply penetrated into the fur brush 10, the brush is deformed or the hairs fall down, and the life of the brush is shortened. Further, it is more preferable that such a sheet or film 25 is formed of a flexible resin material, for example, polyester, in order to avoid a reduction in the life of the fur brush 10.
[0031]
When the scraping plate 14 is provided above the blade 11 along the blade 11 as described above, there is a possibility that the collected toner may stay between the blade 11 and the scraping plate 14. If the collected toner stays and accumulates, the collected toner from the cleaning device 1 overflows, and the surface of the photosensitive drum 1 may be re-contaminated. In order to avoid such inconvenience, it is preferable to provide an opening in the plate surface of the scraping plate 14. The shape and number of such openings are not particularly limited as long as the collected toner can pass through.
[0032]
【The invention's effect】
According to the present invention, the cleaning blade is disposed above the photosensitive drum, and is scraped off together with the blade in a cleaning device including a fur brush, a toner scraping plate from the brush, and a collected toner conveying member. The re-contamination of the fur brush by the toner can be effectively prevented, and the transport efficiency of the collected toner transport member can be improved.
The cleaning device of the present invention is effectively applied to a compact image forming apparatus in which a cleaning blade is disposed above a photosensitive drum.
[Brief description of the drawings]
FIG. 1 is a diagram showing a structure of a cleaning device of the present invention.
FIG. 2 is a diagram showing a position of a tip of a cleaning blade of the cleaning device of the present invention.
[Explanation of symbols]
1: cleaning device 2: photosensitive drum 5: cleaning housing 10: fur brush 11: cleaning blade 14: scraping plate 15: recovery spiral 25: toner scraping auxiliary film or sheet

Claims (5)

A cleaning device for removing toner remaining on the photosensitive drum after transferring the toner image formed on the photosensitive drum,
A cleaning blade that is in contact with the drum at a position above a horizontal line passing through the center of the photoconductor drum, and that is disposed upstream of the cleaning blade with respect to the rotation direction of the photoconductor drum, and is in contact with the photoconductor drum A fur brush provided so as to rotate in the same direction at the contact nip portion with the drum, a scraping plate for scraping off the toner attached to the fur brush, and toner collected by the cleaning blade. And a conveying member for conveying,
The scraping plate extends along the cleaning blade at a distance from the cleaning blade, and a tip of the scraping plate is in contact with the fur brush,
The transport member is arranged on the upper surface of the scraping plate,
A cleaning device, wherein an auxiliary sheet or film for scraping off toner is arranged so as to contact the fur brush so as to partition a space between the conveying member and the fur brush. The cleaning device according to claim 1, wherein the auxiliary sheet or the film is in contact with the fur brush so that only one surface thereof is in contact with the fur brush so as to be shallow. The cleaning device according to claim 1, wherein an opening is formed in the scraping plate. 4. The cleaning device according to claim 1, wherein the scraping plate is located between the cleaning blade and the transport member. 5. 5. The cleaning blade according to claim 1, wherein an angle θ at which a straight line connecting a contact point with the photosensitive drum and the center of the photosensitive drum forms a horizontal line is in a range of 45 to 135 degrees. A cleaning device according to claim 1.

Images