JPS60112084A - Cleaning device - Google Patents

Abstract

PURPOSE:To remove foreign matter properly while preventing the influence of the rubbing operation of an elastic roller against the surface of an image carrier upon residual toner by arranging the elastic roller at the downstream side of a cleaning blade. CONSTITUTION:A cleaning mechanism 6 consists of the 1st cleaning mechanism equipped with the cleaning blade 8 and the 2nd cleaning mechanism equipped with an elastic cleaning roller 11. The residual toner is removed from the surface of a photosensitive body 1 with the cleaning blade 8, but flat foreign matter such as fine paper powder and talc remains and reaches the 2nd cleaning mechanism 6b. The elastic roller 11 turns at a relative speed with the surface of a photosensitive body 1, and the foreign matter is removed by its sliding friction operation, carried along the surface of the roller 12, and removed at a scraper 12. Therefore, the foreign matter is removed properly without exerting any influence upon the residual toner.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus using an electrostatic photographic process, and particularly to a cleaning apparatus.

In this divine image forming device, it is used as a cleaning means to remove residual toner and other foreign matter that accumulates after transfer for +41J days! I' consisting of 11 sexes 4A
Those that use J-La are conventionally known as f-L for those that use liquid developers, but for dry development systems that use powdered toner, for example USl).
As seen in No. 3838472, there are some sealing devices used to prevent leakage of toner from the cleaning device 1°'1'; Use a weak force to remove particles other than toner, such as fine paper dust generated from transfer paper, rosin precipitated from paper, talc, or other particles generated near the high-tL pressure corona discharge area and deposited on the image bearing surface. Effect 1 of removing foreign substances such as corona products was extremely insufficient.

Therefore, it has been proposed to remove the above-mentioned foreign substances along with the toner by rubbing an elastic roller more strongly against the surface of the image carrier.

(For example, I:,!l Publication No. 48-43342).

However, in this case, if the roller is placed upstream of a cleaning blade that is shared with such an elastic roller, -C residual toner may be deposited on the surface of the image carrier due to the friction between the roller and the image carrier surface. It is press-contacted and forms a cloud shape, and a part of this is the cleaning blade Eel+ '[i'
/: When the toner is accumulated in the image carrier and the blade is relaxed, the toner fuses and forms a linear high-resistance layer f('r) in the longitudinal direction of the blade. An unsuitable toner image is formed in this area and appears as a black line on the image. Recently, micro-encapsulated toner has been used to fix with light pressure. However, when such toner is applied to an external object by rubbing a conventional elastic roller on the surface of an image carrier,
There was a risk that the toner would be fused to the surface due to pressure between the roller and the surface, resulting in deterioration of image quality.

The present invention has been made in order to cope with the above-mentioned situation, and in a cleaning device using a cleaning blade or the like, an elastic roller is disposed on the downstream side of the blade when viewed in the running direction of the image carrier. This allows the cleaning device to properly remove foreign substances such as paper dust, precipitated rosin, Merck, and corona products without affecting the residual toner by the rubbing action of the roller on the surface of the image carrier. This is what we provide.

Embodiment C of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 schematically shows the main parts of a copying machine to which a cleaning device according to the present invention is applied, in which a photoconductive layer on the surface of a photoreceptor 10 formed in the shape of a rotating cylinder is uniformly charged by a charger 2; The electrostatic latent image formed by irradiating this with the light image 7 becomes a transferable toner 1g4 (elephant) by the developing device 3.
The toner image is transferred to the transfer portion 4 guided to the transfer site having the transfer electrode 5, and at this time, toner that does not contribute to the transfer or foreign matter such as paper dust, talc, or corona products generated in the image forming process is removed. It adheres to the surface of the photoconductor, reaches the cleaning device 6, and is removed from the surface of the photoconductor,
Thereafter, the above-mentioned process will be repeated.

The cleaning device 6 consists of a first cleaning mechanism equipped with a cleaning blade 8 as shown, and a second cleaning mechanism equipped with an elastic cleaning roller 11 as described below.

Next, the above-mentioned cleaning device 6 will be explained.
First cleaning mechanism 6akl: As is well known, it is equipped with a cleaning blade 8 made of an elastic phase, and is used to mainly scrape off residual toner remaining on the surface of the photoreceptor after being transferred. In this case, the toner is sufficiently removed, but the fine paper powder, talc, etc. generated from the transfer and ablation process in which the cleaning blade is usually used are not removed sufficiently by the cleaning blade because they have a flat shape. Furthermore, since corona products adhere firmly to the surface of the photoreceptor, it is also difficult to easily remove them with a blade.

Therefore, at a position beyond the first cleaning mechanism, the surface of the photoreceptor reaches the second cleaning mechanism 6b with foreign substances other than toner mainly attached thereto. A cleaning roller 12 made of an elastic material is disposed in the cleaning mechanism 6b, and this roller rotates at a speed relative to the surface of the photoreceptor 1, and the elastic roller is in pressure-sliding contact with the surface of the photoreceptor 1. ing.

Talc, corona products, etc. remaining on the surface of the photoreceptor 1 are removed by the sliding action of the surface of the elastic roller 11, and these foreign substances are conveyed to the surface of the roller by the YD]L
to reach the position of the scraper 12 and scrape the roller surface.
L.

It is necessary to configure the elastic clinic roller 11 to avoid the above-mentioned disadvantages of those using the above-mentioned known elastic rollers, and for this purpose, in the present invention,
It consists of two layers: an inner layer and an outer layer, and the inner layer is a sponge layer with low hardness, and the outer layer is made of solid rubber with a high hardness.

When the cleaning roller comes into pressure and sliding contact with the sensing element, the load on the drive system increases, causing image blurring, so it is better to use a sponge roller for F vehicles to avoid increasing the load on the roller. Such fines can easily clog 1.
9 and cannot be removed even with a scraper, and in the end, the surface of the photoreceptor may have to be rubbed with 9, which may have the opposite effect.

Low-hardness urethane rubber used in solid reed rollers uses anti-aging agents, which can damage the photoreceptor. Do not avoid the risk of damaging the photoreceptor.

In the above embodiment, the inner layer 11b is made of Noricon sponge, the outer layer is made of solid silicone rubber, and the hardness of the roller is 20 to 4.0 (ASKERC charge m 500
Good results were obtained by setting the nip 11 at the time of pressure contact to 1 to 6 M, and by setting the cleaning roller's circumferential speed to 50 to 300% of the circumferential speed of the photoreceptor.

The circumferential speed of the leaning roller is 1 on the surface of the photoreceptor.
- The larger it is compared to LK, the more the direction of rotation is the second.
Although the direction shown in the figure is indicated by the arrow, it will be even more effective if the direction is reversed.

The reed scraper 12 uses an insulated roller, and by rubbing the surface of the roller with the opposite polarity to that of toner and other foreign matter to be removed by friction with the cleaning roller, foreign matter can be removed electrically and more efficiently. It is possible to capture the information accurately. Of course, for this reason, it is obvious that the cleaning roller should also be completely finned.

The reason why the 1,111 type cleaning roller of the present invention can effectively remove paper dust, Merck, corona products, etc. is because the surface of the photoreceptor is removed by the cleaning roller, and along with this, impurities can also be removed. The polarity of the charge caused by the frictional charging of the cleaning roller described above is made negative by appropriately selecting the materials of the roller and the scraper, and the talc is electrostatically transferred to the roller 111j in relation to the charging characteristics of talc (in the positive electrode direction). The deposits on the surface of the photoconductor are removed due to several reasons, such as the viscosity of the cleaning roller or the fact that the cleaning roller is more active than the photoconductor and the deposits are transferred to the roller 11111. considered to be a thing.

Further, in the above-described embodiment, the inner layer is made of silicone rubber and the outer layer is made of solid silicone rubber, but the present invention is not limited to this.
It is obvious that the inner layer has low hardness and does not need to be a sponge, as long as it is of a type that does not form a high resistance layer on the surface of the photoreceptor.

It is easy to understand that the leaching of anti-aging agents and unreacted Noricon oil as mentioned above will not be a problem because the outer layer is stable (two-layered).The outer layer is a highly hard solid material. As mentioned above, it is preferable to use a high-resistance material to improve the electrostatic traction action.In addition to silicone rubber, other materials such as urethane rubber and CR can be The rubber phase of a rubber band can be used, and it is also possible to form a single polyethylene or polyester resin into a tube shape and use it as the outer layer.

Since the present invention has the configuration described above, the residual toner, etc. on the surface of the image carrier is first removed by the cleaning blade, and then the elastic cleaning blade is used to remove paper powder, Merck, etc. Since corona raw 1 removes foreign substances such as water, it reduces the burden of toner processing on Cleani/Glora.
jK decrease 1. In addition to suppressing the increase in the load on the drive system, it also prevents the generation of the aforementioned loud toner on the surface of the image carrier despite the rollers being in pressure contact, and effectively removes paper dust, talc, and corona products. 1IiII completely prevents image deterioration, and since the toner in the casing is removed before the cleaning roller, there is no fusion even when using microcapsule toner, greatly extending the life of the image carrier. This greatly contributes to obtaining high-quality images that can be maintained over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a side view schematically showing the main parts of a copying machine to which the present invention is applied, and FIG. 2 is a top view showing the configuration of the cleaning device of the present invention. 1...Photoreceptor, 6...Cleaning device, 6a...
First cleaning (G structure, 6b...second cleaning mechanism, 8...cleaning blade, 11...cleaning roller. Patent applicant: Gyanon Co., Ltd.

Claims (1)

[Claims] A first gluing means including a cleaning blade which is disposed close to the moving image carrier and whose edge comes into pressure contact with the cleaning blade;
11. A cleaning device including, downstream of the first cleaning device, a second cleaning device including an elastic cleaning roller that comes into pressure contact with the surface of the image carrier.