JPH0128528Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rubber blade for a cleaning device that cleans fine substances such as toner and paper powder adhering to an image holding member.

Cleaning methods include a blade method in which an elastic blade is pressed against the surface of the image holding member D, a fur brush method, etc., but the blade method is smaller, causes less toner to scatter around the cleaning device, and is suitable for high-speed processes. It is commonly used because it is suitable.

Among the blade types, there are a rubber plate blade 1 as shown in FIG. 1 and a tip blade in which a rubber plate is attached to the tip of a metal holder 2 as shown in FIG.

In the former case, since the tip portion that contacts the image holding member and the base portion connected thereto are integrated, the rubber hardness is the same at each portion. However, the part of the blade tip that comes into contact with the image holding member for cleaning, and the base part other than the blade tip, which requires strength to press the tip with a certain amount of pressure, have to have appropriate rubber hardness, rubber thickness, etc. Since these conditions do not necessarily match, intermediate compromise conditions are used.

Although the tip blade was devised to correct the above-mentioned drawbacks, the holder made of a thin metal plate tends to cause non-uniform contact pressure in the longitudinal direction of the blade. In this respect, an elastic member such as rubber can more easily absorb strain at the attachment portion of the blade and various pressure inconsistencies than a thin metal plate.

The present invention aims to eliminate each of the drawbacks of the above two conventional examples, and aims to provide a cleaning blade that is inexpensive and has a simple structure.

FIG. 3 shows one embodiment of the present invention, in which a tip portion 4 of the tip of the rubber blade contacts the image holding member and a base portion 5 other than the tip presses against the tip of the blade.
This is a configuration with different rubber hardness.

For example, in the case of polyurethane rubber, the blade tip 4 has a thickness of 2 to 3 mm and a shore hardness of 40°, and the other base portion 5 has a hardness of 60°.

With this configuration, the rubber hardness that matches the friction coefficient of the surface D of the image holding member can be selected. That is, when the blade is made of a material with a small coefficient of friction, the rubber hardness is made small, and when the blade is made of a material with a large coefficient of friction, the rubber hardness is made large, so that the rubber material can be selected to maximize the cleaning performance.

On the other hand, by selecting the rubber hardness of the base portion 5 other than the blade tip 4 so as to uniformly press the blade tip against the image holding member, appropriate pressure can be applied to the blade tip.

This is because if the base part 5 is made to have a hardness of about 40 degrees, which is the same as the tip part 4, the base part 5 will be soft, and if you try to apply enough pressure to the blade, the rubber blade will curve greatly, and the blade will become an image holding member. It hits the belly, causing a phenomenon of reversal and becoming inappropriate.

On the other hand, the tip part 4 should be set to a hardness of about 60 degrees, for example, to which the above pressure can be applied to the base part 5, or the thickness of the blade should be set to 5 degrees.
When the blade is relatively thick, such as ~10 mm, it is difficult to bring the blade into contact with the image holding member D with light pressure.

Therefore, in the present invention, the hardness of the rubber blade is optimized so that the hardness of the blade tip 4 and the hardness of the other base 5 are optimized for each function, and it is possible to improve the cleaning performance and reduce the pressing pressure of the blade. It is effective in making it substantially uniform.

The above embodiment shows an example in which the entire blade is made of the same component and has different hardness.
The tip portion 4 and the base portion 5 that come into contact with the image holding member may be formed of different rubber materials. For example, if the tip part 4 is made of polyurethane rubber with a hardness of 40 degrees and the base part 5 is made of silicone rubber with a hardness of 70 degrees, polyurethane rubber with excellent wear resistance can be used for the sliding part, and the base part is made of polyurethane rubber with better weather resistance. By using silicone rubber with excellent properties, the hardness of the rubber does not change significantly even when the environment changes, especially the temperature, and the blade can always be pressed against the image holding member with uniform pressure.

[Brief explanation of the drawing]

FIGS. 1 and 2 are perspective views of conventional blades, and FIG. 3 is a perspective view of the blade of the present invention. 1 is a plate blade, 2 and 3 are tip blades, 4
is the tip and 5 is the base.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a rubber blade for a cleaning device that presses an elastic member against the surface of an image holding member to clean toner remaining on the surface of the image holding member, the blade is in the form of a thin plate. What is claimed is: 1. A cleaning blade, characterized in that the cleaning blade has a hardness lower than that of a base portion continuous to the tip portion, and is integrally formed with the hardness of the tip portion that contacts the image holding member. (2) The cleaning blade according to claim (1), wherein the blade has a tip portion and a base portion made of the same material. (3) The cleaning blade according to claim (1), wherein the tip portion and the base portion of the blade are made of different materials.