JPH0451075A - Cleaning device for image forming device - Google Patents

Abstract

PURPOSE:To always keep the state of friction between a blade edge and the surface of an image carrier to be a reduced state by burying abrasive minute particles in the vicinity of an abutting edge on the image carrier of a cleaning blade. CONSTITUTION:The abrasive minute powder whose desirable average particle diameter is in the range of 1.5 - 0.2mum and which is composed of an abrasive substance is buried in the vicinity of the abutting edge on the image carrier 1 of the cleaning blade 3. Consequently, the frictional force is reduced by making an effective area where the cleaning blade 3 is brought into contact with the image carrier 1 small, and a very small gap is formed between the blade edge 3 and the image carrier 1, so that lubricity is improved by the ingress of many minute particles acting as a lubricant. Thus, the frictional force between the cleanomg blade 3 and the image carrier 1 is always stably kept at a low value.

Description

Detailed Description of the Invention (1) Purpose of the Invention (Field of Industrial Application) The present invention relates to an image forming apparatus that uses an electrostatic transfer process, such as an electrostatic copying machine or a printer, and particularly to a cleaning device thereof. It is.

(Prior art and problems to be solved) In a well-known image forming apparatus that repeats the process of transferring a transferable toner image formed on the surface of a moving image carrier onto a transfer material such as paper, the process of transferring a transferable toner image onto a transfer material such as paper during transfer is difficult. Since it is unavoidable that some toner remains on the image bearing member without the transfer, it is essential to sufficiently remove this residual toner each time transfer is performed to obtain a good quality image.

Cleaning methods for this purpose include fur brushes,
A number of cleaning webs, cleaning blades, etc. have been proposed in the past, but one method involves pressing one edge of a cleaning blade made of an elastic material such as rubber against the surface of an image carrier, thereby scraping off residual toner. The structure is simple, takes up little space, is cost-effective, and has an excellent toner removal function, so it is widely used in practice.

This type of cleaning method usually uses a counter method in which the cleaning blade is placed opposite the running direction of the image carrier, but since the friction between the cleaning blade and the image carrier is generally large, Especially when the device is first installed or when images with low toner consumption are continuously printed, the blade edge may vibrate or the blade may turn over, resulting in poor cleaning and deterioration of image quality. could not be avoided.

In order to avoid such problems, it has been proposed to apply fine powder such as polyvinylidene fluoride to the blade edge and the surface of the image carrier, but with this method, the fine powder gradually decreases as it is used. Therefore, it is difficult to constantly and stably supply the appropriate amount of fine powder to the blade edge over a long period of time.On the other hand, the friction between the blade edge and the surface of the image carrier is Since the friction changes in various ways depending on the state, it is difficult to perform cleaning under stable friction conditions at all times, and it is not possible to completely prevent the blade from turning over.

Furthermore, the blade may turn over due to changes in the characteristics of the blade due to changes in the environment, changes in the lubricity of the fine powder provided, etc.

The present invention has been made in order to cope with the above-mentioned current situation, and the present invention has been made by embedding fine powder for lubricating in the vicinity of the edge of the cleaning blade that faces the surface of the image carrier, thereby reducing the effect of the lubricant in the environment. The object of the present invention is to provide a cleaning device that can stably perform cleaning over a long period of time without causing blade curling or chatter.

(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 in which one edge of the cleaning blade is brought into contact with an image bearing member. It is characterized in that microparticles are embedded near the edges.

With this configuration, in a cleaning device equipped with a cleaning blade of an image forming apparatus, it is possible to maintain the frictional force between the cleaning blade and the image carrier at a stable and low value at all times, thereby preventing blade turning. It is possible to effectively prevent the occurrence of chatter and perform good leaning over a long period of time.

(Description of Embodiments) The attached drawing is a schematic side view of a cleaning device suitable for applying the present invention, and shows a cleaning device 2 in parallel with and close to a cylindrical image carrier 1 rotating and traveling in the direction of arrow A. After a toner image is formed on the surface of the toner image and transferred to the transfer material by the action of a primary charger (not shown), an image signal applying means, a developing means, a transfer means, etc., the toner image is transferred to the image carrier until the end. It is assumed that the residual toner remaining on the surface reaches the cleaning device 2 and is cleaned by the cleaning blade 3 disposed in the device.

In the cleaning device having such a configuration, according to the present invention, the cleaning blade 3 is made of an abrasive substance and has an average particle size of 1.5 μm to 0.0 μm, especially near the edge of contact with the image carrier 1. It is made by embedding fine powder of about 2 μm.

With this configuration, the effective area where the cleaning blade actually contacts the image carrier is reduced, thereby reducing the frictional force, and a minute gap is formed between the blade edge and the image carrier. Therefore, a large amount of fine particles that act as a lubricant enter into this, improving lubricity.

In this case, the above effect is promoted by selecting an abrasive substance as the particles to be embedded in the blade edge and appropriately setting the particle size.

Furthermore, since particles are embedded in the cleaning blade only at the end that contacts the image carrier, there is no particular change in the characteristics of the blade as a whole, and the list price for the original cleaning function is not included.

The material for the fine particles embedded in the blade edge is A.
130a, SIC%CeOz, strontium titanate, and other materials with excellent abrasive properties, and the average particle size thereof is, as mentioned above, 0.2 to 1.
The range is 5 μm.

To measure the average particle size, observe the powder with a scanning electron microscope, measure the diameter of each particle, take the average value of 20 points, repeat this operation 3 times (repeat, and then take the average value) .

If the particle size exceeds 1.5 μm, the gap between the blade and the surface of the image carrier becomes too large, which may lead to cleaning problems. decreases significantly.

The means for embedding the above-mentioned fine particles in the blade edge will be explained.

Urethane rubber, which has been widely used as a material for cleaning blades, is formed by adding a catalyst such as dibutyltin silafrate to urethane rubber raw materials such as polyol compounds and isocyanate compounds, and then thermosetting the mixture in a mold.

In this case, the cleaning blade is completed by molding the blade with the powder applied to the portion corresponding to the blade edge in the mold.

Next, an experimental example of the present invention will be explained.

Experimental Example 1 A cleaning device such as a cleaning blade was placed in contact with an image carrier having a diameter of 80φ and having a photosensitive layer made of an organic semiconductor in the counter direction. A powder of Iμm A1□03 was used.

A test of 1000 sheets of solid white images was conducted using such an apparatus.

Then, a similar test was conducted in an environment of 30° C. and 90% RH.

The results are shown in the table below, including the following experiments.

Experimental Example 2 An experiment was conducted under the same conditions as above, except that CeO□ with an average particle size of 0.9 μI was used as the powder.

Comparative Example 1 Paper was passed under the same conditions as in Experimental Example 1, except that a normal blade without embedded powder was used as the cleaning blade.

Comparative Example 2 Paper was passed under the same conditions as Experimental Example 1 except that the particle size of the A1□03 powder was 3.0 um.

Comparative Example 3 Paper was passed under the same conditions as Experimental Example 1 except that the particle size of the A1□03 powder was 0.1 μm.

The above results are summarized in the table below.

(The following is a blank space) Engraving of the drawings (no changes to the content) (3) As described in detail, the present invention provides a cleaning device equipped with a cleaning blade in which the cleaning blade hits the image carrier. Because fine particles with abrasive properties are embedded near the contact edge, the friction between the blade edge and the surface of the image carrier can be maintained at all times in a reduced state, and the shavings generated from the image carrier can be removed from the vicinity of the blade edge. Since it has the function of holding the blade at a constant temperature, it is possible to maintain a stable cleaning function over a long period of time without causing blade curling, chatter, etc., and is significantly effective in obtaining high-quality images.

[Brief explanation of the drawing]

The accompanying drawing is a schematic side sectional view of a cleaning device suitable for applying the present invention. 1...Image bearing body, 2...Cleaning attachment, thread sales, formalities (method) Commissioner of the Japan Patent Office, November 1990, 100 1) Moon Yi 1, Case Indication Patent Application Hei 2- 157646 No. 2, Name of the invention Cleaning device for image forming apparatus 3, Relationship with the person making the amendment Case Applicant address name Canon Co., Ltd. 4゜

Claims (2)

[Claims] (1) A cleaning device for an image forming apparatus in which one edge of a cleaning blade is brought into contact with an image bearing member, wherein microparticles are embedded near the edge of the cleaning blade. (2) The cleaning device according to claim 1, wherein the average particle diameter of the microparticles is within the range of 0.2 to 1.5 μm.