JPH0193780A - Cleaning device for image forming device - Google Patents

Abstract

PURPOSE:To prevent toner from being sent back to an image carrier by forming a partitioning wall, which is approximated to a toner gathering plate but is not brought into contact with this plate, in a position close to the toner gathering plate. CONSTITUTION:A toner gathering plate 4 rotated in the direction of an arrow (a) is arranged above a cleaning blade 3 in the running direction of a photosensitive body 1, and the toner scraped by the blade 3 is sent to a toner storage part and is discharged out of a device by a screw 5. A partitioning wall 8 is arranged near and above the gathering plate 4. This partitioning wall 8 is made of materials having proper strength, and its edge nearest to the gathering plate 4 is not brought into contact with the outside end part of the gathering plate 4 and the gap between them is narrowed as much as possible. Thus, the sent-back toner is surely prevented from hindering the function of the cleaning device 2 or from being scattered out to stain each part in the image forming device.

Description

Detailed Description of the Invention (1) Purpose of the Invention (Field of Industrial Application) This invention relates to an image forming apparatus that uses an electrostatic recording process, such as an electrostatic copying machine or a printer, and particularly to a cleaning device for the same. .

(Prior Art and Issues to be Solved) Includes a step of transferring a transferable toner image formed on the surface of an image carrier to a sheet-like transfer material, mainly paper, and then separating this transfer material from the image carrier. In well-known image forming apparatuses, 1. During transfer, it is inevitable that some toner remains on the image carrier without contributing to the transfer, so this residual toner must be thoroughly cleaned before starting the next image forming process. It is necessary to do so.

A number of cleaning means have been proposed and implemented in the past, but the remaining toner can be removed using a cleaning blade made of an elastic material such as rubber. !
Drop-off devices are widely used because they have a simple structure and an excellent toner removal function.

FIG. 3 schematically shows an example of a cleaning device in such an image forming apparatus, in which a cleaning device is installed in the vicinity of a cylindrical image carrier l extending perpendicular to the plane of the paper and rotating in the direction indicated by the arrow. A cleaning device 2 is arranged in parallel.

A cleaning blade 3 is attached to the cleaning device, and one free edge of the cleaning blade 3 is in pressure contact with the surface of the image carrier 1. The toner that has not been transferred to the transfer material at the transfer site (not shown) is scraped off.

The scraped toner is disposed inside the casing of the cleaning device, and is delivered to a toner storage section on the back side of the casing (the side opposite to the cleaning blade) by a toner collection plate 4 that rotates in the direction of arrow a. , and are discharged from the casing by the conveying screw 5.

In such a device, when there is little toner in the cleaning device, toner processing can be carried out suitably, but
For example, if the transfer efficiency decreases in a high-temperature, high-humidity environment and a large amount of toner is sent into the cleaning device, the situation shown in Figure 4 will occur, and some of the toner will be collected by the rotating collection plate. The toner tends to be sent back toward the image carrier again, and toner accumulates on the back surface of the cleaning blade near the edge, obstructing the blade's action and causing cleaning failures. There is a risk that it may escape and contaminate other parts.

In order to avoid such drawbacks, for example, as shown in FIG. 5, a partition plate 7 made of an elastic plate material such as a polyester film is disposed so as to slightly touch the radial tip of the collection plate 4, and the toner Some proposals have been made to prevent the collection board 4 from being sent back.
With each rotation of the partition plate, an opening is formed between the partition plate and the partition plate, so it is impossible to completely prevent the backflow of toner.Furthermore, especially in a low humidity environment, the fluidity of the toner increases and causes it to scatter. If the situation is easy, the partition plate
The vibration caused by the contact with the collection plate causes a large amount of toner to scatter, which has the drawback of escaping from both ends of the cleaning device to the outside.

The present invention has been made to deal with such a situation, and is configured such that the toner collected from the image carrier into the cleaning device by the cleaning blade is conveyed to the toner storage section by a rotating toner collection plate. An object of the present invention is to provide a cleaning device that effectively prevents collected toner from being sent back toward an image carrier or a cleaning blade and maintains a stable cleaning function over a long period of time. It is something to do.

(2) Structure of the invention (technical means for solving the problem and its operation) In order to achieve the above object, the present invention includes a part that is equipped with a cleaning means such as a cleaning blade to remove toner from the image bearing member; A cleaning device comprising: a portion for storing or discharging toner conveyed from the portion to the outside of the cleaning device; and a rotating toner collection plate located between these two portions for feeding toner from the former portion to the latter portion. The apparatus is characterized in that a partition wall is formed at a position close to the toner collecting plate between the two parts so as to be close to the collecting plate and not to come into contact with it.

With this configuration, even if a large amount of toner is introduced into the cleaning device, this toner is effectively prevented from being sent back toward the image carrier, and the partition wall prevents the rotation of the collection plate. Since there is no one who actively scatters the toner by vibration, it is possible to prevent poor cleaning and contamination of the inside of the image forming apparatus due to toner escape.

(Description of Embodiments) FIG. 1 shows a side view of the main parts of an embodiment in which the present invention is applied to a copying machine equipped with a rotating cylindrical photoreceptor.
A cleaning device 2 is disposed in parallel with and close to a photoreceptor l that extends perpendicularly to the plane of the paper and rotates in the direction of the arrow.

It goes without saying that the photoreceptor is provided with a charger, an image signal applying means, a developer, a transfer charger, and other members necessary for forming a background image, but these are not included in the present invention. are not directly related, so they are all omitted.

One edge of the cleaning blade 3 attached to the cleaning device is in pressure contact with the surface of the photoreceptor 1, and at a transfer site (not shown), residual toner remaining on the photoreceptor without contributing to transfer is removed. As the photoreceptor rotates, it is scraped off when it reaches the cleaning blade position.

A toner collection plate 4 that rotates in the direction of arrow a is disposed on the upstream side of the cleaning blade when viewed in the traveling direction of the photoconductor, and collects the toner scraped off by the cleaning blade 3 into a toner storage section on the back side. At this position, the toner is further discharged to the outside by the conveying screw 5.

A partition wall 8 is disposed close to the toner collecting plate 4 and above it in the drawing. The partition wall is made of a material with appropriate strength such as metal or hard synthetic resin, and its edge near the toner collection plate 4 does not come into contact with the outer edge of the collection plate and maintains a gap between the two. should be made as narrow as possible.

With this configuration, if the transfer efficiency decreases for some reason, a large amount of toner accumulates inside the cleaning device, and the toner is sent back toward the cleaning blade 3 by the toner collecting plate 4. Even in such a situation,
Due to the presence of the partition wall 8, most of the toner, except for the amount that overflows from the small gap between the partition wall 8 and the collection plate, is blocked from being transported and does not go toward the cleaning blade. Even if the fluidity of the toner decreases and the toner tends to solidify, it is destroyed between the toner collecting plate and the partition wall and can be smoothly transported to the toner storage section, so the toner presses against the cleaning blade and does not perform the cleaning function. This can prevent the toner from causing any adverse effects or escaping to the outside and contaminating various parts. Especially in a low humidity environment, the toner that is agitated and scattered by the collection plate 4 is also blocked by the partition wall and can be cleaned. It is also possible to prevent a situation where the blade reaches the side where the blade is located and further escapes to the outside.

In the above embodiment, a case was described in which the partition wall was made of a material with appropriate hardness; however, this partition wall was able to resist the pressure of the toner that was fed back toward the blade from the back side within the cleaning device. If a hard foreign object is present in the cleaning device and gets caught in this partition wall, it may be made of an elastic material such as a polyester thin plate. It is also possible to prevent the collecting plate 4 from being damaged.

In addition, instead of forming the partition wall with an elastic material as in the above case, the toner collection plate may be formed with a similar elastic material, or both the partition wall and the toner collection plate may be formed with a similar elastic material. It is easy to understand that it can have a significant effect.

Further, by forming the partition wall integrally with the casing of the cleaning device, costs can be reduced.

FIG. 2 shows another embodiment of the present invention, in which the basic structure of the cleaning device is the same as that shown in FIG. The end edge side facing 4 has a concave surface portion 9° along the cylindrical surface defined by the tip of the collecting plate.

By forming in this manner, when the rotating toner collecting plate is located at a position where the partition wall is separated, toner can be prevented from being sent back through the large gap formed between the rotating toner collecting plate and the partition wall.

Although an embodiment in which the present invention is applied to a copying machine has been described above, it is easy to understand that the present invention is not limited to such a device and can be applied to various image forming apparatuses. Dew.

(3) Effects of the Invention As explained above, the present invention has a structure in which the toner removed from the image carrier is conveyed to the toner storage section in the cleaning device by a rotating toner collecting member disposed in the cleaning device. In this structure, a partition wall is disposed as close as possible to the toner collecting member to prevent the collected toner from being sent back to the cleaning means, image carrier, etc. It is possible to reliably prevent the sent toner from interfering with the function of the cleaning means or from escaping to the outside and contaminating various parts of the image forming apparatus, which contributes to obtaining high-quality images. It's large.

[Brief explanation of the drawing]

FIG. 1 is a side view of a main part showing an embodiment in which the present invention is applied to a copying machine, FIG. 2 is a side view of a main part of another embodiment of the present invention, and FIGS. 3 to 5 are a known cleaning device. FIG. 3 is a side view of the cleaning device for explaining the operation of the cleaning device. 1...Photoreceptor, 2/...Cleaning device, 3...
Cleaning blade, 4... Toner collection plate, 5...
・Transportation screw, 811... Bulkhead.

Claims (4)

[Claims] (1) A part equipped with a cleaning means that directly interacts with the image carrier to remove residual toner, a part located on the opposite side of the image carrier to store or discharge the collected toner, and A cleaning device comprising: a toner collection plate located between the two parts for conveying the toner collected in the former part to the latter part; A cleaning device in which a partition wall is formed in a direction that is close to the partition wall without interfering with the partition wall and prevents the toner from being sent back from the latter part to the former part. (2) The cleaning device according to claim 1, wherein the partition wall is made of an elastic material. (3) The cleaning device according to claim 1, wherein the partition wall is formed integrally with the casing of the cleaning device. (4) Claim 1, wherein the toner collecting plate comprises a rotating plate member, and the partition wall has a concave surface extending circumferentially along the outer periphery of the rotating cylindrical surface of the toner collecting plate. cleaning equipment.