JPS62269189A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent respective parts in an image forming device from being contaminated with simple constitution by positioning a scoop sheet nearby a rotary magnetic roller arranged on the upstream side of a cleaning member. CONSTITUTION:A gathering member 4 and the scoop sheet 7 are arranged closely to each other and the magnetic force of a magnet roller is made large enough. Consequently, toner which is part of toner carried by a photosensitive body and scraped by the scoop sheet 7 to fall outside it sticks on the external surface of the sheet with the magnetic force of the magnet roller as shown by T without falling as it is. Further, the toner is moved gradually toward the edge of a sleeve on which the photosensitive body abuts according to the rotation of the magnet roller as well as toner falling on the sleeve and further moved beyond the abutting edge, so that the toner is gathered in a cleaning device. Consequently, none of the scraped toner is scattered on respective parts to contaminate the inside.

Description

Detailed Description of the Invention (1) Purpose of the Invention (Field of Industrial Application) This invention relates to image forming apparatuses that use magnetic toner and utilize an electrostatic recording process, such as electrostatic copying machines and printers, and particularly to image forming apparatuses that use magnetic toner and electrostatic recording processes. The present invention relates to a cleaning device.

(Prior Art and Problems to be Solved) A well-known image forming method in which a transferable toner image is formed on the surface of an image carrier and the process of transferring this to a sheet-like transfer material, mainly paper, is repeated. In the apparatus, it is essential to remove residual toner remaining on the image carrier each time transfer is performed to prepare for the next process.

Various methods such as fur brushes and cleaning blades have been proposed as means for cleaning residual toner, but as is well known, those using these cleaning means are Usually, a part is opposed to the image carrier, and toner is once guided to this part and then removed with a blade, brush, or the like. For this reason, it is not always easy to configure a cleaning device so that the toner removed from the image carrier by the cleaning means is reliably held within the casing and does not scatter to the outside.

This will be explained with reference to FIG. 2, which is a schematic side sectional view showing a typical example of such a known cleaning device, which uses a cleaning blade as a cleaning means. There is.

Image carrier (hereinafter referred to as photoreceptor) formed into a rotating cylinder shape
A cleaning device 20 is arranged close to lO,
One edge of the free end of the cleaning blade 30 disposed thereon is in pressure contact with the surface of the photoreceptor.

Residual toner that has not been transferred to the transfer material at a transfer site (not shown) and has arrived at the cleaning device while adhering to the surface of the photoreceptor is scraped off from the surface of the photoreceptor by the cleaning blade 30, so that the toner is removed into the casing. However, when the toner is collected by gravity like the device shown in the figure, the opening of the cleaning device is located upstream of the blade (as viewed in the direction of travel of the photoreceptor). , toner is inevitably scattered to the outside through the opening.

For this reason, as shown in the figure, a scooping sheet 50 made of Mylar or the like is arranged at the most upstream part of the opening, and its edge is lightly brought into contact with the surface of the photoreceptor to remove the residual toner carried by the photoreceptor. Then, the toner scraped off by the blade is captured by a scooping sheet and collected at a predetermined location within the cleaning device.

Note that the reference numeral 40 in FIG. 1 is a conveying screw for discharging the collected toner. - With such a configuration, it is extremely difficult for the scoop sheet to initially pass all of the incoming toner and to reliably capture the toner removed by the blade. It is not easy to completely prevent the toner from having a scraping effect on the toner.

For this reason, the toner removed from the photoreceptor by the scooping sheet falls on the outside of the sheet, and this is dissipated into the image forming apparatus, resulting in the inconvenience of contaminating various parts.

It is easy to understand that the same situation applies to cleaning devices that use brushes as cleaning means.

The present invention has been made to deal with such a situation, and even in a cleaning device that uses a scooping sheet as described above, there is a possibility that the toner scraped by the sheet may scatter to various parts within the image forming apparatus. It is an object of the present invention to provide a cleaning device that does not cause contamination of the device or deterioration of image quality due to the contamination of the device.

(2) Structure of the invention (technical means for solving the problem and its operation) In order to achieve the above object, the present invention provides a cleaning device configured to collect waste toner using a scoop sheet. This device is characterized in that a magnetic roller is arranged inside the cleaning device and near the scoop sheet.

With this configuration, it is possible to prevent the toner from falling and to forcibly guide the toner into the cleaning device, thereby preventing the toner from scattering to various parts within the image forming apparatus.

(Description of Embodiments) FIG. 1 is a schematic side sectional view showing an embodiment in which a cleaning device according to the present invention is applied to a copying machine equipped with a cylindrical photoreceptor that rotates in the direction of arrow A.

A cleaning device W12 is disposed adjacent to the photoconductor 1, and one free edge of an elastic cleaning blade 3 provided thereon is in pressure contact with the surface of the photoconductor.

In addition, around the photoreceptor, there are a main charger for charging the surface photosensitive layer, an image signal writing means for forming an electrostatic latent image, a developer for visualizing the latent image, and a developing device for visualizing the image. There are members necessary for image formation, such as a transfer charger that transfers the image to the transfer material and a separation charger that separates the transfer material from the photoreceptor, but these are not directly related to the present invention, so a description of them will be omitted. Omitted.

Residual toner that does not contribute to transfer at a transfer site (not shown) and remains on the surface of the photoconductor reaches the cleaning blade 3 as the photoconductor rotates, is scraped off by the blade, and falls into the casing of the cleaning device. do.

Inside the cleaning device, there is a collection member 4 consisting of a magnetic roller 4a that rotates in the direction of the arrow on the upstream side of the cleaning blade when viewed in the traveling direction of the photoreceptor, and a sleeve 4b made of a non-magnetic material surrounding the magnetic roller 4a. The tip of the photoconductor may be loosely in contact with the photoreceptor, or
A scoop sheet 7 made of mylar or other suitable material is provided, which is placed in close proximity.

Therefore, the toner scraped off the photoreceptor by the cleaning blade falls onto the sleeve, is then conveyed in the direction of arrow B by the action of the rotating magnetic roller, and is removed from the sleeve by the scraper 6.

The toner thus collected is discharged to the outside by the conveying screw 5 as required.

By arranging the collection member 4 and the scoop sheet 7 close to each other and making the magnetic force of the magnetic roller sufficiently large, some of the toner conveyed by the photoreceptor can be absorbed by the scoop sheet 7.
The toner that is scraped by the scraper and spilled to the outside thereof does not fall as is, but is attached to the outer surface of the scooping sheet by the magnetic force of the magnetic roller, as shown by the symbol T.

Furthermore, as the magnetic roller rotates, this toner is
Similar to the aforementioned toner that has fallen onto the sleeve, the toner is gradually moved toward the edge of the sleeve that contacts the photoreceptor, and is received in the cleaning device beyond the edge.

Since the cleaning device described above works as explained above, regardless of whether a scoop sheet is used, the scraped toner will scatter to various parts inside the image forming apparatus, contaminating the inside or deteriorating the image quality. There is no invitation.

Note that the sleeve of the collecting member of the above device is not an essential requirement, and although a cleaning blade is used as the cleaning material in the above description, a fur brush may also be used with the same effect. It will be readily understood that the present invention is also applicable to forming apparatuses.

(3) Effects of the Invention Since the present invention has the configuration described above, it has the effect of effectively preventing contamination of the inner part of an image forming apparatus and obtaining high-quality images with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an embodiment in which the present invention is applied to a copying machine, and FIG. 2 is a side view for explaining the configuration and operation of a known cleaning device. 1..Φ photoconductor, 2..phi. cleaning device, 3..
Cleaning blade, 4 parts... Collection member, 4a...
Magnetic roller, 6... scraper, 7... scooping sheet,

Claims (1)

[Scope of Claims] A cleaning device for removing residual magnetic toner from the surface of an image carrier that moves relative to the cleaning member, the scooping sheet being positioned near a rotating magnetic roller disposed upstream of the cleaning member. A cleaning device configured as follows.