JP2973604B2 - Developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an electrophotographic process, such as a printer, a facsimile or a copying machine, and more particularly to a developing apparatus used in an image forming apparatus.

[0002]

2. Description of the Related Art FIG. 3 is a longitudinal sectional view of a conventional developing device. As shown in the figure, a sheet-like thin layer forming member 10
1 is a developing device main body 10 which is a holding member 106 and a screw 107.
8 is fixed to the wall.

The toner 105 is conveyed to the supply roller 103 by the rotation of the stirring member 104 and adheres to the roller-shaped toner carrier 102.

[0004] Toner 10 adhered to toner carrier 102
5 passes through the thin layer forming member 101 as the toner carrier 102 rotates. At that time, the toner 105 was regulated by the thin layer forming member 101 to be a thin layer, and was charged.

[0005]

[Problems to be solved by the invention] The conventional developing device described above
In order to obtain a stable image without density unevenness,
A uniform thin layer and uniform charging on the toner carrier 102
It is necessary to form a toner layer having
When the layer forming member 101 is brought into contact with the toner carrier 102
And the contact pressure and contact width are uniform in the longitudinal direction of the toner carrier.
Must be given evenly.

For this reason, mounting of the thin layer forming member 101
High accuracy is required for position and mounting angle,
It took a lot of work and productivity was not good.

Further, a screw 107 for fixing the thin layer forming member 101 to the developing device main body 108 and a holding member 10 for holding the thin layer forming member 101 in the longitudinal direction of the toner carrier 102 are provided.
6 are required, the number of parts is increased, and the cost is increased.

An object of the present invention is to provide a developing device which solves the above-mentioned problems.

[0009]

To achieve the above object, a developing device according to the present invention is a one-component developing device for visualizing an electrostatic latent image on an image carrier with charged toner,
A toner carrier for adhering toner on the image carrier; and a thin layer forming member that regulates and reduces the thickness of the toner layer attached to the toner carrier, wherein the thin layer forming member has a cylindrical shape.
Ku forms a quadrangular prism shape, and consists of flexible material from the surface layer to the center portion, in Runomi fitted in a recess provided in the wall of the developing device main body surrounding the toner carrying member, the toner carrying member It is the one that is elastically attached to and held .

Further, the thin layer forming member, have a hollow in the center, and a tube-shaped end faces are not closed
Things.

[0011]

According to the present invention, the structure for mounting the thin layer forming member is of a fitting type so that the mounting is facilitated and the number of parts is reduced.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention, and FIGS. 2 (a) and 2 (c) are perspective views of a thin layer forming member.

In FIG. 2, the thin layer forming member 1 has a function of uniformly thinning the toner 5 conveyed on the toner carrier 2, and therefore, as shown in FIGS. It has a cylindrical shape or a quadrangular prism shape, and is filled with a flexible material such as silicon rubber, urethane rubber, nitrile butylene rubber, or natural rubber from the surface layer to the center.

Note that the sectional shape is not limited to the illustrated sectional shape as long as the sectional shape in the longitudinal direction of the toner carrier 2 is uniform.

The thin layer forming member 1 is fitted into a recess 7 provided on the wall surface of the developing device main body 8 surrounding the toner carrier 2,
The toner 5 is regulated by contacting and bending with the toner carrier 2 and applying a preferable pressing force to the toner carrier 2.

Since the thin layer forming member 1 is structured to be fitted into the recess 7, it does not require a holding member or screws, and is easy to assemble.

The thin layer forming member 1 is made of a flexible material, so that a uniform pressing force can be applied to the toner carrier 2 without requiring high precision in the mounting position and the like.

The toner 5 is guided from the supply roller 3 to the toner carrier 2 by the stirring member 4 and passes through the thin layer forming member 1 so that the toner 5 is uniformly charged and formed into a uniform thin layer. You.

The toner 5 formed in a thin layer on the toner carrier 2 adheres to an electrostatic latent image on a photoconductor 6 such as an OPC, which is an example of an image carrier, and is developed. The toner 5 adhered to the electrostatic latent image is transferred to a printing medium (not shown), and a good image without density unevenness can be formed.

(Embodiment 2) When a thin layer forming member made of a flexible material shown in FIGS. 2A and 2C is used, the material is limited to a low-hardness flexible material. As shown in (b) and (d), by having the cavity 6a in the center,
It is possible to reduce elasticity even in a high-hardness flexible material, and to adjust the porosity so as to adjust the pressing force to a preferable value and to apply a uniform pressing force to the toner carrier 2. Becomes possible.

[0022]

As described above, the developing device of the present invention has a thin-layer forming member made of a flexible material, and the thin-layer forming member is held by being pressed against the toner carrier. Since the contact pressure and contact width applied to the toner carrier by the thin layer forming member can be uniformly and uniformly applied, and a uniform thin layer of toner can be formed,
A stable image without density unevenness can be obtained.

Further, since the thin layer forming member is made of a flexible material and has a structure to be fitted into the depression, it does not require high accuracy for mounting, and the number of adjustment and inspection steps is reduced, thereby improving productivity. Since a member for fixing the thin layer forming member to the developing device main body is not required, low cost can be realized.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention.

FIG. 2 is a perspective view showing a thin layer forming member.

FIG. 3 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thin layer forming member 2 Toner carrier 3 Supply roller 4 Stirring member 5 Toner 6 Photoconductor 7 Depression 8 Developing device main body

Claims (2)

(57) [Claims] 1. A one-component developing apparatus for visualizing an electrostatic latent image on an image carrier with charged toner, comprising: a toner carrier for adhering toner on the image carrier; A thin layer forming member that regulates the attached toner layer to make it thinner, wherein the thin layer forming member has a cylindrical or quadrangular prism shape,
And made of a flexible material from the surface layer to the center portion, in Runomi fitted in a recess provided in the wall of the developing device main body surrounding the toner carrying member, resilient contact to the toner carrier, Contact
A developing device which is characterized in that those preliminary held. 2. The thin layer forming member has a cavity in the center.
With a tube shape that is not closed at both ends
The developing device according to claim 1, characterized in that.