JPS61212880A - cleaning equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Object of the Invention (Field of Industrial Application) The present invention relates to an image forming apparatus using an electrophotographic process, such as an electrophotographic copying machine or a printer, and particularly to a cleaning apparatus for the image forming apparatus.

(Prior art and problems to be solved) A well-known image forming apparatus that repeats the process of removing residual toner remaining on the surface of an image carrier after transferring a transferable toner image formed on the surface of the image carrier to a transfer material. It has been well known that a two-component developer consisting of toner and carrier is used to form a toner image.

When performing magnetic brush development using such a two-component developer, the magnetic plan formed on the sleeve surface in the developing device and rubbed against the image carrier surface only needs to be formed of toner. Regardless of the theory, in practice it is difficult to completely prevent the presence of some carrier particles.

In this way, the carrier particles are brought to the surface of the image carrier through the magnetic plan, and when they adhere thereto, the image carrier particles reach the position of the cleaning blade disposed in the cleaning device to remove the residual toner. There is a risk that the particles may enter the blade edge portion that is in pressure contact with the image bearing member and damage the surface of the image carrier.

In order to avoid such inconvenience caused by the presence of carriers, in addition to the cleaning blade, a fixed magnet is placed inside a rotating sleeve to attract and remove the carriers attached to the surface of the image carrier. A structure has already been proposed in which a fixed magnet is disposed within a fur brush roll, and the carrier is wiped off from the surface of the image bearing member by a fur plan, and the carrier is collected by the magnet.

However, with the former type, the only force that acts on the carrier is the magnetic force of the magnet, so the collection efficiency of small particle carriers is poor, and such a cleaning blade is in pressure contact with the image carrier. There was a risk that the damage would reach the edges and damage the edges or the surface of the barge image carrier, resulting in deterioration of image quality.

Increasing the size of the magnet to improve collection efficiency is
This was impractical because it would lead to an increase in the size of the cleaning device.

In the latter case, the presence of the fur brush weakens the effect of the magnet on the carrier, and in order to reduce this distance, the fur brush must be strongly pressed against the image carrier, or the bristles of the brush must be shortened. This is not preferable since the brush becomes stiff and may damage the surface of the image carrier.

The present invention has been made in order to cope with such a situation, and in an image forming apparatus using a two-component developer, the carrier particles discharged from the developing device are sufficiently removed, and the carrier particles are removed from the image bearing member or cleaning grade edge. It is an object of the present invention to provide a leaning device that prevents damage such as, and contributes to obtaining stable images over a long period of time.

(2) Structure of the invention (technical means for solving problems and their effects), J2ft
In order to achieve the object No. 41, in the present invention, a rotating sleeve and a fur brush are disposed in the cleaning device, and in particular, the peripheral speeds of the fur plan and the image carrier are set to be approximately the same, and the fur It has a system to wipe away the toner collected by the brush and the gear rear.

With this configuration, kinetic energy is applied to the carrier particles on the surface of the image carrier to weaken their adhesion to the surface, and then the carrier particles are attracted and collected by magnetic force, making it possible to effectively remove the carrier particles. It is possible.

(Description of Embodiments) The attached drawing is a side view showing a part of an image forming apparatus equipped with a cylindrical image bearing member 1 rotating in the direction of arrow A. Cleaning device 2
is installed.

As is well known, the area around the image carrier 1 includes a negative charger, an exposure section for projecting a light image, a developing device containing a developer, and a transfer charger for transferring a toner image onto a transfer material. Although there are containers and the like, these are not directly related to the present invention, so their explanation will be omitted.

Inside the multi-leaning device 2, a cleaning blade 3 made of an elastic material such as urethane rubber is disposed with one edge pressed against the surface of the image carrier by means such as a spring 3a.

A carrier collecting member 4 having a non-magnetic sleeve 4b having a fixed magnet 4a therein is disposed upstream of the cleaning blade 3 when viewed in the running direction of the image carrier. The member 4 can be rotated in the direction of arrow B,
A gap of 1 to 15 holes is provided between the image carrier and the surface of the image carrier.

A scraper 6 for scraping off the collected carriers is disposed in contact with the carrier collecting member 4.

Although the illustrated fixed magnet 4a has two poles, it is needless to say that the structure is not limited to this as long as a collection effect can be obtained, and it is preferable to use magnets with a diameter of 800 Gauss each.

A fur brush roller 5 is disposed further upstream of the carrier collecting member 4. The material of the brush may be rayon or any other flexible material, and it is preferable that the bristles be as long as possible and as stiff as possible. The brush roller 5 is arranged so that the nip width is 7 to 8 divisions from the image carrier, and
It is preferable that the surface of the image carrier is rubbed by the belly portion of the fiber, rather than the tip of the fiber.

Furthermore, a plate-shaped wiping member 7 is provided so as to enter the brush roller appropriately.

It is also assumed that the sleeve 4b and the plan roller 5 are run at substantially the same or slightly higher speeds in the directions of arrows B and C, respectively, at positions facing the image carrier 1.

With this structure, an external force is applied to the carrier adhered to the surface of the image bearing member, and of course the carriers that would be removed on the spot are brushed off, but this is not the main purpose. Make it easy to release from the surface.

The carriers, which are easily released in this way, then reach the position of the carrier collecting member 4 and are reliably collected by its magnetic force.

The cleaning blade 3 naturally functions to remove toner, and since the carrier on the surface of the image carrier has already been removed on the upstream side, there is no risk of damaging the blade.

Note that the wiping member 7 that wipes off the carrier attached to the fur brush roller 5 or the toner scraped off from the cleaning blade and captured on the roller 5 is formed as a plate-like member made of a conductive material such as stainless steel or copper. , it is preferable to eliminate static electricity from the fibers of Fabran.

The toner scraped off by the cleaning blade reaches the fur brush roller 5 and is further brushed off by the wiping member 7, and the carrier captured by the gear rear collecting member 4 is scraped off by the scraper 6. It is assumed that the fluid is accumulated in a reservoir within the body, and is further discharged to the outside of the casing by means such as the screw conveyor 8, if necessary.

(3) Effects of the Invention The present invention is configured as shown below, and by using a fur brush roller and a magnetic gear collecting part in combination, image formation using a two-component developer is possible. In the apparatus, the carrier particles discharged from the developer are efficiently removed and prevented from reaching the cleaning blade, so that the carrier particles do not reach the cleaning blade and thereby damage the image carrier surface, and also prevent the carrier particles from reaching the cleaning blade. The plano roller also uses the abdomen of the brush to rub the surface of the image carrier, which prevents damage to the surface of the image carrier caused by the brush, which contributes to extending the life of the image carrier and stabilizing the image. It's large.

Furthermore, the air flow generated by the rotation of the fur brush roller actively guides the scattered toner toward the inside of the cleaning device, so that it is possible to prevent the toner from escaping to the outside of the cleaning device.

[Brief explanation of the drawing]

The accompanying drawing is a side sectional view of a cleaning device according to the invention. 1... Image carrier, 2... Cleaning device, 3...
・Cleaning grade, 4...Carrier collection member,
5...Fur brush roller, 6...Scraper, 7
...wiping member

Claims (1)

[Claims] A cleaning member is provided that comes into contact with the surface of the moving image carrier, a magnetic carrier collecting member is disposed close to the cleaning member on the upstream side as viewed in the running direction of the image carrier, and a fabric roller is further provided on the upstream side of the cleaning member. A cleaning device that is arranged so that the inner part of the fibers of the brush rubs against the surface of the image carrier.