JPS60218681A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent the moisture absorbing action and the photographic fog due to stuck hygroscopic foreign matters by making it possible to apply and rub a hydrophobic liquid and to remove a part of this liquid. CONSTITUTION:A wiping mechanism 11 which removes a silicone oil is provided in the downstream side of a cleaning roll 9. The wiping mechanism consists of a supply roll 11a around which a web 12 consisting of a non-woven cloth for wiping the silicone oil is wound, a take-up roll 1b which winds up the web, and a pressing roll 11c which presses and rubs the web part stretched between both rolls to the surface of a photosensitive body. The take-up roll pulls the web successively in propor speeds by a proper driving means (not shown in the figure), and a fresh surface of the web is brought into contact with the surface of the photosensitive body. A part of the silicone oil which is oozed from a cleaning roll 9 and is stuck to the surface of the photosensitive body is removed by the wiping mechanism 11, and a minute quantity of the silicone oil is applied on the surface.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Purpose of the Invention The present invention relates to an image forming apparatus such as an electrophotographic copying machine or a printer thereof, and particularly to a cleaning apparatus therefor.

A well-known image forming method in which a transferable toner image formed on the surface of an image carrier is transferred to a transfer material mainly made of paper, and the process of cleaning residual toner remaining on the surface of the image carrier without contributing to the transfer is repeated. In apparatuses, cleaning means for removing residual toner using a cleaning blade made of an elastic material such as urethane rubber has been widely used in practice because it is small and compact and has an excellent toner removal function.

However, although such a leaning blade is effective in removing residual toner on the surface of the image carrier, it mainly removes precipitates such as rosin and talc deposited from the paper used as the transfer material, or in the image forming apparatus. This method is not always sufficient to remove deposits on the surface of the image carrier, such as corona products caused by the presence of high-potential members, and such deposits may remain on the surface of the image carrier.

This type of deposit absorbs water in a high humidity environment and lowers its resistance, which disturbs the electrostatic latent image, resulting in image deletion and deterioration of image quality.

In order to avoid such drawbacks, it has been proposed that a cleaning roller made of an elastic material such as silicone rubber or silicone sponge is brought into contact with and rubbed against the image carrier to remove the above-mentioned deposits.

The cleaning roller made of an elastic material as described above is not limited to silicone, but silicone rubber is not durable and the silicone oil that oozes out from it is applied to the surface of the image carrier, so This method is suitable because it is easy to remove deposits, and furthermore, since the surface of the image carrier is covered with silicone oil and exhibits hydrophobic properties, it is possible to prevent deposits from becoming low in resistance and to prevent deterioration of image quality.

Although it varies depending on the environment, it is preferable for the surface of the image carrier to be coated with a small amount of silicone oil to the extent that it does not cause cracks in the image. In the previously proposed device, it is of course difficult to control the amount of silicone oil that oozes out, and there is a risk that an excessive amount of oil may be applied. Care must be taken to avoid such limitations, and we have not yet been able to obtain a product that can maintain good functionality over a long period of time.

The present invention has been completed in order to cope with the current situation, and is an image forming apparatus equipped with a means for applying silicone oil to the surface of an image carrier. It is an object of the present invention to provide a leaning device that prevents image blurring by always and controllably applying an appropriate amount of oil to the surface of an image carrier so that it can be removed.

(2) Structure of the Invention In order to achieve the above object, the present invention provides a cleaning device for an image forming apparatus that uses an electrostatic process. In a device equipped with a means for oozing and applying silicone oil, an appropriate amount of silicone oil can be applied to the surface of the image carrier by disposing a wiping member such as a web or a fabric brush to wipe off at least a part of the applied oil. By allowing the oil to dry, a cleaning device is constructed that does not cause fogging on the image and does not cause image blurring due to an excess amount of oil.Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic side view of an embodiment in which a cleaning device according to the present invention is applied to a copying machine, and is shown by the arrow A.
After the surface of the photoreceptor 10, which rotates continuously in the direction, is uniformly charged by the charger 3, a light image of a document (not shown) is irradiated at the position of the arrow X to form an electrostatic latent image, and then the developing device The latent image is visualized by the toner supplied by 4.

On the other hand, a transfer material (not shown) approaching the photoreceptor along the transfer material path 5 receives the toner image in close proximity to the toner image at the position of the transfer charger 6, and is connected to the separation electrode 7a and the separation roller 7b.
The photoreceptor is separated from the photoconductor and conveyed to a fixing device (not shown) by means such as the above.

Residual toner remaining on the surface of the photoconductor without being transferred to the transfer material at the transfer position reaches the cleaning device 2 as the photoconductor l rotates, and the residual toner is removed by a cleaning blade 8 attached to the cleaning device. It is stirred up.

゛In the illustrated cleaning device, a cleaning roller 9 made of an elastic material such as silicone rubber is in pressure contact with the surface of the photoreceptor on the upstream side of the cleaning blade 8, and is moved in the direction of the arrow shown in the figure or in the opposite direction by a drive source (not shown). The toner scraped off by the cleaning blade is conveyed to a toner storage section in the cleaning device by rotating and sliding at a relative speed to the photoreceptor, and foreign substances such as corona products are removed by rubbing.

The toner brought to the storage section is discharged out of the cleaning device by an appropriate means such as the screw conveyor 10, if necessary.

The cleaning roller 9 can be made of a suitable elastic material such as silicone rubber or silicone sponge, but the illustrated one has an inner layer 9b made of silicone sponge and an outer layer 9a made of solid silicone rubber to adjust the elasticity.
I am using something consisting of.

In a cleaning device having such a configuration, as mentioned above, there is a risk that silicone oil may ooze out from the cleaning roller made of silicone rubber and cause fogging on the image. For this reason, in the illustrated embodiment, a wiping mechanism 11 for removing silicone oil is provided downstream of the cleaning roller 9.

The wiping mechanism includes a supply roller lla wound with a web 12 made of nonwoven fabric or the like for wiping off silicone oil;
It consists of a take-up roller Ilb that winds up the web, and a suppression roller Ilc that presses and slides the part of the web suspended between both rollers onto the surface of the photoreceptor. The take-up roller is configured to sequentially pull the web at an appropriate speed by an appropriate driving means (not shown) so that a new surface of the web comes into contact with the surface of the photoreceptor.

In the illustrated embodiment, the housing 2a of the cleaning device
Although the wiping mechanism is disposed outside of the housing 2a, it is of course possible to configure the wiping mechanism inside the housing 2a or integrally with the housing 2a.
The degree of pressure contact (c) shall be determined as appropriate depending on the amount of silicone oil exuding from the cleaning roller.

With this structure, at least a portion of the silicone oil that oozes out from the cleaning roller 9 made of silicone rubber and adheres to the surface of the photoreceptor is removed by the wiping mechanism 11, so that fogging does not always occur on the surface of the photoreceptor. You can apply a small amount of silicone oil.

FIGS. 2 and 3 show other embodiments of the present invention, in which parts corresponding to those shown in FIG. Only that part is shown.

In the device shown in the second figure, a fur brush 13 is disposed downstream of the cleaning roller 9 of the cleaning device, and is configured to remove a portion of the silicone oil on the surface of the photoreceptor. . Further, in the case shown in FIG. 3, a support base 14a extending in the axial direction of the photoreceptor 1 is disposed on the downstream side of the cleaning roller 9, and an oil adsorption member 14b such as a non-woven fabric is stretched over this support base 14a. It is configured to remove a portion of the silicone oil by rubbing it on the surface of the photoreceptor.

Although not shown in the drawings, the support 14a shown in FIG. It is also possible to configure the support base and the suction member to rotate slowly.

Above, the cleaning device includes a cleaning blade,
Although a cleaning roller made of an elastic material such as silicone rubber for removing foreign substances such as corona products has been described, it goes without saying that the present invention is not only applicable to a cleaning device having such a configuration. Therefore, an example of a cleaning device having another configuration will be described below.

FIG. 4 is a side view of main parts showing another embodiment in which the present invention is applied to a copying machine, in which the photoreceptor 1 and other corresponding parts are denoted by the same reference numerals, and the image There is no particular difference in the forming process from that shown in FIG.

The cleaning device 2 shown in FIG. 4 is provided with a magnetic roller 15 on the upstream side of the cleaning blade 8, and by rotating the roller itself or a non-magnetic sleeve (not shown) that covers it, the cleaning blade The toner scraped off by the magnet roller 15 is collected and conveyed to the toner storage section, and the toner is rubbed on the surface of the photoreceptor by a magnetic brush formed by the presence of the magnet roller 15, thereby adhering to the surface of the photoreceptor along with the remaining toner. It is designed to remove minute pieces of paper, dust, etc. Additionally, it is well known that such a leaning device is particularly suitable for copying machines that use magnetic toner.

Even in a cleaning device configured as described above, as in the case described above, there is a risk that corona products, deposits such as robins from transfer paper may adhere to the surface of the photoreceptor, and image deletion may occur due to lower resistance due to moisture absorption. I can't escape it.

In such a cleaning device, in the one shown in FIG. 4, an elastic roller 16 made of silicone rubber is placed downstream of the cleaning blade and rotates in an appropriate direction so as to have a relative speed to the circumferential surface of the photoreceptor. Let me rub it,
The roller is configured to apply silicone oil impregnated onto the surface of the photoreceptor. This allows the above-mentioned first
To prevent image smearing as in the case shown, but to prevent excessive oil from being present on the photoreceptor surface, a roller similar to that shown in FIG. A wiping mechanism 11 is provided, and a roller 1 made of silicone rubber is provided.
A portion of the silicone oil is removed by a wiping mechanism according to the amount of silicone oil exuded in step 6, and the amount of oil is adjusted so that a trace amount of oil is present so as not to cause fogging due to an excessive amount of oil.

Although not shown, it is of course possible to use an appropriate wiping mechanism such as those shown in FIGS. 2 and 3 above.

In FIG. 5, instead of the elastic roller 16 in the one shown in FIG. 4, a web 18 made of a nonwoven fabric impregnated with silicone oil is used as the feed roller 17a.

The pressure roller 17c2 is suspended from a take-up roller 171) and is rubbed on the surface of the photoreceptor 1 to supply silicone oil to the photoreceptor, which is then adjusted by the wiping mechanism 1.

FIG. 6 shows still another embodiment of the present invention, in which the cleaning device 2 includes a cleaning blade 8 and a magnet roller 15.

In this embodiment, an oil application blade 19 made of silicone rubber is pressed against the surface of the photoreceptor 1 on the downstream side of the cleaning blade, and further downstream, part of the silicone oil applied to the surface of the photoreceptor is removed. A roller 20 is placed in pressure contact with the surface of the photoreceptor, and the roller 20 is rotated in either direction to rub the surface of the photoreceptor.

It is assumed that oil and other foreign substances removed by this roller are removed by a scraper 20a.

The roller 20 may be made of urethane, polyolefin, fluorine resin, fur brush, or the like.

FIG. 7 shows still another embodiment of the present invention, in which a cleaning device 2 disposed close to the photoreceptor 1 includes:
A magnetic roller 15 is provided in the same way as in the previous embodiment, and a cleaning blade 21 made of silicone rubber is used to scrape off residual toner and apply oil to the surface of the photoreceptor. A suitable wiping mechanism 11 is provided to adjust the amount of oil.

In the embodiments shown in FIGS. 4 to 7, an oil application member and a wiping mechanism for wiping the oil are provided separately from the cleaning device. Of course, it can also be stored and arranged together with other members.

In addition, the substance applied to the photoreceptor is not limited to silicone oil, but may include a hydrophobic, non-volatile liquid,
It is easy to understand that it can also be used by impregnating sponge, felt, etc.

(3) Effects of the Invention Since the present invention has the above-described structure and function, by applying it to an image forming apparatus, it is possible to remove hygroscopic substances that adhere to the surface of an image carrier by applying silicone oil or the like. It is possible to prevent the hygroscopic action of foreign substances and the resulting reduction in resistance, thereby preventing image smearing, and also to prevent "fogging" caused by the presence of an excessive amount of the oil on the surface of the image bearing member. This has the effect of stably obtaining high-quality images over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view of the main part showing the case where the present invention is applied to a copying machine; FIGS. 2 and 3 are side views of the main part showing a modified embodiment of the apparatus shown in FIG. 1; FIG. 4 is a partially cutaway side view of the main part showing the case where the present invention is applied to a cleaning device different from that in FIG. 1, FIG. 5 is a side view of the main part showing a modified embodiment of the same, and FIG. , FIG. 7 is a side view of a main part showing still another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Photoreceptor, 2... Cleaning device, 9... Elastic cleaning roller, 11.14... Wiping mechanism, 1
5... Macnet roller, 16... Silicone rubber roller, 18... Oil application mechanism, 20... Wiping roller, 21... Silicone rubber blade. Patent applicant: Canon Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] Means for rubbing and applying a hydrophobic liquid onto the surface of a moving image carrier; and wiping means for removing a portion of the liquid on the downstream side of the means when viewed in the running direction of the image carrier. The cleaning device that comes with it.