JPS6267572A - Developing device - Google Patents

Abstract

PURPOSE:To utilize triboelectrification caused by rubbing of a developer and to attract and remove light paper powder and dust mixed in the developer by disposing the tip of a paper powder removal brush composed of a highly elastic fabric made of a flexible insulating high molecular material so that it can burry in the flow of a developer scraped by a scraper. CONSTITUTION:The developer 3 uniformly softened by agitating devices 5 and 6 is adsorbed on the surface of a magnet roll 4 rotating clockwise, and its crest is unified by the head of a regulating plate 7. A photosensitive body 1 selects the developer which develops its latent image. The developer 3 resident on the surface of the magnet roll 4 after the development is scraped by the scraper 8. The fabric bundle 10 of the paper powder removal brush electrostatically changes by rubbing the developer 3, and adsorbs the paper powder mixed in the developer 3. The flow of heavy paper powder is interrupted by the bundle 10 of the paper powder removal brush, and floats up the upper surface of a bank 3a. The filter 9 of the paper powder removal brush collects the paper powder floating on the upper surface of the bank 3a by clinging to remove said powder from the developer 3.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a developing device for an electrostatic transfer copying machine or the like, which is office equipment.

(Prior Art) In recent years, the image quality of electrostatic transfer copying machines has significantly improved, and their resolution, fine line reproducibility, and no-ft tone reproducibility have approached those of general printing machines. However, when a latent image is transferred to paper, paper dust adhering to the photoreceptor etc. gets mixed into the developer, accumulates as the number of copies increases, and appears on the image, causing a reduction in image quality. was.

A conventional developing device will be explained with reference to an enlarged cross-sectional view of main parts in FIG. In the conventional developing device, a magnet (not shown) is built into the opening of a developing container 2 facing the photoreceptor 1, and a magnet roll 4 rotates clockwise to convey the developer 3 to the photoreceptor 1. Two agitating devices 5 and 6 are provided in the developer 3 reservoir, and a regulating plate 7 is provided above the magnet roll 4 to keep the developer 3 adsorbed thereon in a uniform manner.
At the bottom is the developer 3 that has completed the development process (magnetic).

- Scrapers 8 for scraping off the surface of the wheels 4 are respectively disposed.

To explain the operation of the developing device configured in this way, the developer 3 uniformly mixed in the stirring devices 5 and 6 is
The photoreceptor 1 is attracted to the surface of the magnet roll 4 rotating in a clockwise direction, and the head of the regulating plate 7 makes the spikes uniform.
The latent image is developed. The developer 3 remaining on the surface of the magnet roll 4 after performing the role of development is scraped off by the scraper 8 and falls into the storage section of the developer container 2.
The process understood by stirring devices 5 and 6 is repeated again.

(Problems to be Solved by the Invention) However, in this configuration, since the developing device does not have a function to remove paper dust from the developer 3, it is difficult to generate paper dust in the paper feeding and paper conveyance system. There is no choice but to provide a pressing device or a removing device, and there is a problem in that if the developer 3 becomes contaminated with paper dust or the like, the entire amount must be replaced.

The present invention solves the above-mentioned problems and provides a developing device including a paper powder removing device within the developing container.

(Means for Solving the Problems) In order to solve the above problems, the present invention removes paper powder made of flexible and highly elastic fibers from the flow of developer scraped off with a scraper. The paper dust removal brush is arranged so that the tip of the brush can fit inside.

(Function) With the above configuration, each fiber of the paper dust removal brush rubs against the developer and becomes electrically charged, thereby adsorbing paper dust in the developer.

Further, since dust other than paper dust is also absorbed at the same time, the developer is cleaned in parallel with the development process.

In addition, if the shape of the fibers of the paper dust removal brush is processed in advance using a heat press or the like to make it difficult to undergo plastic deformation, the above-mentioned cleaning effect can be enhanced and sustained.

(Example) An example of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is an enlarged sectional view of main parts of a developing device according to the present invention.
A magnet roll 4, which has a built-in magnet (not shown) in the opening of the developer container 2 facing the photoconductor 1 and rotates clockwise to convey the developer 3 to the photoconductor 1, serves as a reservoir for the developer 3. There are agitating devices 5 and 6 at the bottom of the magnetic roll 4, and a regulation plate 7 for keeping the spikes of the developer 3 adsorbed thereon constant at the bottom of the magnet roll 4, and a regulation plate 7 at the top for keeping the developer 3 that has been subjected to the development process by a magnet. A scraper 8 is provided to scrape off the surface of the roll 4. Further, a filter 9 and a fiber bundle 10 are attached to the side wall of the developer container 2 above the scraper 8.
The paper dust removal brush fixed to the fixing plate 11 is connected to the machine screw 12.
The filter 9 is in contact with the surface of the reservoir 3a of the developer 3 flowing on the scraper 8,
The tip of the fiber bundle 10 is adjusted so that it is buried from the surface.

The fibers 10 of the paper dust removal brush are flexible and highly elastic fibers, preferably polyester.

It is made of a polymeric material such as polyamide or nylon (registered trademark) and has a diameter of about 1 μm to 10 μm, is flexible and elastic, and does not impede the flow of the developer. The shape of the fiber M is generally linear as shown in Figure 2 (A), but there are also spiral shapes and second shapes as shown in Figure 2 (B).
A wavy type as shown in Figure (C), or a type made of multiple fibers twisted together into a thread shape as shown in Figure 2) is used. It is desirable that the fiber bundle 10 has a density of 1000 fibers/crn or more.

The paper dust removal filter 9 is a non-woven sheet made of a polymeric material such as polyamide or polyester, or a sheet made of multiple layers of woven fabric, and has a thickness of about 0.5 m to 5 resistant.

The operation of the developing device configured as described above will be explained. The developer 3 that has been uniformly dispersed by the stirring devices 5 and 6 is attracted to the surface of the magnet roll 4 that rotates clockwise, and the spikes of the developer 3 become uniform at the head of the regulating plate 7 and are applied to the photoreceptor 1. The latent image is developed. The developer 3 remaining on the surface of the magnet roll 4 after playing a developing role is scraped off by the scraper 8 and falls onto the scraper 8. The developer 3 scraped off by the scraper 8 is influenced by the magnetic force of the magnet roll 4, and a part of the developer 3 forms a pool 3a on the scraper 8.

On the other hand, the fiber bundle 10 of the paper dust removal brush rubs against the developer 3 and becomes electrically charged, thereby adsorbing paper dust mixed in the developer 3.

Its adsorption power varies depending on the amount of charge, fiber density, and fiber shape, but light paper powder can be captured semi-permanently. The flow of heavy paper dust is obstructed by the fiber bundle 10 of the paper dust removal brush and floats to the upper surface of the reservoir 3a.

The filter 9 of the paper dust removal brush entangles the paper dust floating on the upper surface of the reservoir 3a and removes it from the developer 3. Small dust other than paper powder is also cleaned at the same time.

Paper dust or the like that has been adsorbed or entangled with the paper dust removal plan can be easily cleaned by loosening the machine screw 12 and removing the paper dust removal brush.

In this embodiment, as shown in FIG. 1, the fiber bundle 10 of the paper dust removal brush is washed away by the developer 3, and a gap is created between it and the filter 9 fixed in front of it. Paper powder, etc. floating on the upper surface of the reservoir 3a is caught in this gap, but when the magnet roll 4 stops and the flow of the developer 3 stops, the fiber bundle 10 returns and is caught between it and the filter 9. Since the gap formed in the developer 3 is closed, paper dust and the like caught therein are trapped as they are and do not mix into the developer 3.

In the embodiment, a single paper dust removal plan is used, but a plurality of paper dust removal plans may be arranged.Although a stationary type is used, a means for automatically cleaning the paper dust removal plan by installing it on a rotating shaft may also be provided.

Further, the fiber bundle 10 of the paper dust removal brush may be made of an elastic metal material.

(Effects of the Invention) As explained above, according to the present invention, the tip of the paper dust removal brush made of flexible fibers, especially highly elastic fibers made of an insulating polymer material, can be scraped off with a scraper. By placing it so that it is buried in the flow of developer,
Using the electrical charge generated by friction with the developer, it is possible to adsorb and remove light paper dust and dust mixed in the developer. Also, a non-woven fabric made of polymeric material attached to the front side of the paper dust removal brush A filter using a sheet can remove heavy amounts of paper powder and dust mixed in the developer. Further, paper dust and the like caught by the paper dust removal brush can be easily removed and cleaned, so it is possible to obtain a developing device of excellent quality in which image quality is not degraded by paper dust, dust, etc.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of main parts of a developing device according to the present invention, and FIG.
The figure is an external view with the shape of the fibers used in the paper dust removal brush according to the present invention removed, and FIG. 3 is an enlarged sectional view of the main parts of a conventional developing device. 1... Photoreceptor, 2... Developer container, 3... Developer,
3a... Reservoir, 4... Magnet roll, 5.6.
... Stirring device, 7... Regulation plate, 8... Scraper,
9... Filter of paper dust removal brush, 10... Fiber bundle of paper dust removal brush, 11... Fixing plate of paper dust removal brush.゛Title-7 Figure 1!・・・Kankusai

Claims (6)

[Claims] (1) Flexible elasticity in a developing device equipped with a magnet roll containing a built-in magnet, a regulation plate installed close to the magnet roll, and a scraper installed in contact with the circumferential surface of the magnet roll. A developing device characterized in that a paper dust removal plan made of fibers rich in fibers is disposed such that its tip is buried in the flow of the developer scraped off by the above-mentioned scraper. (2) The developing device according to claim (1), characterized in that a filter made of a non-woven sheet shorter than the fiber bundle is provided at the base of the fiber bundle of the paper dust removal plan. . (3) The paper dust removal plan is made of an insulating polymeric material.
2) The developing device described in section 2). (4) The developing device according to claim (1) or (2), characterized in that the paper dust removal brush uses fibers having a wavy shape. (5) Claim No. (5) characterized in that the paper dust removal plan uses a plurality of fibers twisted together into a thread shape.
The developing device according to item 1) or item (2). (6) The developing device according to claim (1) or (2), characterized in that the paper dust removal plan uses fibers having a spiral shape.