JPH0498274A - Image forming device - Google Patents

Abstract

PURPOSE:To extremely reduce the amount of image on an image carrier stripped off by a developer drawing roll by carrying out prevention of transmitting and slipping of rotational force between an image carrier and the developer drawing roll due to parts of high frictional contact. CONSTITUTION:The sponge roll part 25 is provided with a developer drawing range 25a. The high frictional contact members of the roll 21 are provided with higher elasticity and higher frictional force compared to the roll part 25, and are provided in both edge parts of 25b and 25c of the roll part 25. Knurled part processing members 23 are installed in the drum 1, a retaining part 1a with the photosensitive body 2 is provided in the drum 1, and the processing members 23 are installed in both edges 1aa and 1ab. The transmission of rotational force between the drum 1 and the developer drawing roll 12 is carried out between the processing materials 23 and the contact members 21, and since they pressurize each other in a state of great frictional force, there is hardly any generation of slipping, and rotation is carried out at an equal circumferencial speed. Therefore, there is also hardly any generation of slipping between the photosensitive body 2 and the roll part 25, and since there is hardly any transmission of the rotational force from the photosensitive body 2 to the roll part 25, there is no stripping of toner on the photosensitive body 2 by the roll 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus that performs development by applying a developer to an image carrier on which a latent image is formed.

[Prior Art] Conventionally, a wet-type image forming apparatus that performs development using a developer includes an image carrier 100 and a developer smudge roller 102, as shown in FIGS. 4 and 5, for example. The image carrier shown in FIGS. 4 and 5 is composed of a drum] 04 and a photosensitive paper 106. Developer liquid streak roller 1
02 includes a liquid-absorbing elastic roller 108, a shaft 1]0, and a bearing 1]2. The drum] 04 holds the photosensitive paper 106 by suction and rotates to remove the photosensitive paper 106.
The process of the predetermined development procedure for 06 is sequentially executed. The photosensitive paper 06 forms an electrostatic latent image when exposed by an exposure device (not shown).

When the photosensitive paper 106 on which the electrostatic latent image is formed passes through a developing device (not shown) as the drum 104 rotates, toner particles charged to the opposite polarity to those forming the electrostatic latent image are suspended. The film is developed by being immersed in a developing solution, or by being coated with a developing solution by a developing roller (not shown). Thereby, the electrostatic latent image is made into a visible image.

After the development, the excess developer 114 is removed from the photosensitive paper [06] by a developer stain roller [02]. In other words, the developing solution smudge roller] 02 is in pressure contact with the image carrier 100 at the liquid-absorbing elastic roller 5108, and as the image carrier] 00 rotates, it rotates while in contact with the image carrier [00], causing the excess on the photosensitive paper 106 to be removed. Squeeze out the developer.

[Problems to be Solved by the Invention] However, in the conventional image forming apparatus, since the developer smudge roller 102 rotates due to contact friction with the image carrier]00, the developer smear roller]02 There is a problem in that the toner image formed on the photosensitive paper 106 is peeled off.

By solving the above-mentioned problems, the present invention aims to provide an image forming apparatus in which a toner image formed on an image carrier is hardly peeled off by a developer smudge roller.

[Means for Solving the Problems] As a means for achieving the above object, the image forming apparatus of the present invention is provided by applying a developer to an image carrier on which a latent image is formed, and after development, applying the developer to the image carrier. In an image forming apparatus in which excess developer adhering to the image carrier is removed by rolling a smudge roller, rolling force is transmitted while preventing slip between the image carrier and the developer smudge roller. The gist of the invention is that a high-friction contact portion is provided outside the latent image recording area of the image carrier and/or outside the ripple area of the development ripple roller.

[Function] In the image forming apparatus of the present invention, the rolling force is transmitted between the image carrier and the developer smudge roller by a high friction contact portion provided outside the latent image recording area or outside the smudge area. .

Therefore, the high friction contact portion prevents slippage between the image carrier and the developer smudge roller. As a result, peeling force is not applied to the toner image on the image carrier from the developer smudge roller.

[Embodiment] Hereinafter, an embodiment of a developing device for a wet-type electrophotographic copying machine embodying the present invention will be described in detail based on the drawings. FIG. 1 is a block diagram of a developer smudge roller, FIG. 2 is a block diagram of a wet-type electrophotographic copying machine, and FIG. 3 is a block diagram of a developing device.

First, the configuration of a wet-type electrophotographic copying machine will be described. Second
As shown in the figure, a drum 1 is rotatably supported by a shaft 1a, and a photoconductive sheet-like photoreceptor 2 is supplied to the outer peripheral surface of the drum 1 and held by suction means using negative pressure. Further, at a position facing the outer circumferential surface of the drum, there is a corona charger 3 that charges the photoreceptor 2 by applying an electrostatic charge;
an exposure device 4 that exposes the charged photoreceptor 2 to form an electrostatic latent image; a front bath roller 5 that contacts the photoreceptor 2 to prevent background smearing from the front bath liquid (developer solvent); A wet developing device 6 that develops the photoreceptor 2 moistened with a bath liquid with a developer to visualize the electrostatic latent image, and a static eliminator 7 that removes the electric charge remaining on the photoreceptor 2 after development. They are sequentially arranged along the rotational direction of the drum 1.

As shown in FIG. 3, the developing device 6 includes a storage tank 8, in which a developer 9 is stored. Development electrode 1
0 is a concave surface 10 on an arc formed in the storage tank 8 and facing the outer peripheral surface of the drum 1 with a slight gap at its upper end.
A is provided. A pump 11 is provided at the lower end of the developing electrode]O.
o and is supplied to the photoreceptor 2 on the drum 1.

A developer smudge roller 12 made of an elastic material is rotatably disposed within the storage tank 8 via a support 3. The developer smudge roller] 2 and the drum 1 are provided with a rolling force transmission section 16, which will be described later. The developer smudge roller 12 is connected to the spring 14
is pressed against the outer circumferential surface of the drum 1. With the above-mentioned configuration, the photoreceptor 2 is developed with the developer 9 from the developing electrode]O, and the surplus developer remaining on the photoreceptor 2 after the development is removed by the developer smudge roller]2. .

Next, the rolling force transmission section 6 will be explained based on FIG. The rolling force transmission section 16 includes a roller high friction contact member 21,
The knurling member 23 is also provided.

The roller high friction contact member 21 is disposed on the developer smudge roller 12 . The developer smudge roller] 2 includes a sponge roller portion 25, a shaft 27, and a bearing 29.

The sponge roller portion 25 has a developer streak area 25 a corresponding to the size of the photoreceptor 2 . The roller high friction contact member 21 has higher elasticity and higher frictional force than the sponge roller portion 25.
are arranged at both ends 25b and 25c. The roller high friction contact member 2] and the sponge roller portion 25 are formed to have substantially the same outer diameter.

The knurling member 23 is disposed on a drum. The drum] is provided with a holding portion [a] for the photoreceptor 2, which is an area for recording a latent image. The knurling member 23 is disposed at both ends of the holding portion aa and lab.

The knurling member 23 and the holding portion]a are formed to have substantially the same outer diameter. The photoreceptor 2 described above corresponds to the image carrier in the claims.

As described above, the drum 1 having the above-mentioned rolling force transmission section 6 and the developer smudge roller 12 are pressed against each other with a predetermined pressing force, and as the drum rotates, the developer Liquid smudge roller ] 2 also rotates.

In the wet-type electrophotographic copying machine described above, the rolling force between the drum and the developer smudge roller 12 is transmitted between the knurling member 23 and the roller high friction contact member 21. Further, since the drum] and the developer smear roller 12 are pressed together with a large frictional force, they rotate at the same circumferential speed with almost no slippage.

As a result, there is almost no slip between the photoreceptor 2, which rotates together with the drum 1, and the sponge roller section 25, and moreover, there is little slippage between the photoreceptor 2 and the sponge roller section 25.
There is also almost no transmission of rolling force to 5. Therefore, the toner on the photoreceptor 2 is not stripped off by the developer smudge roller 12. As a result, the extremely excellent effect of improving the copying quality of the wet-type electrophotographic copying machine is achieved.

Note that the present invention is not limited to the above-mentioned embodiments, and can be implemented in various forms without changing the gist of the present invention. For example, instead of providing high-friction parts on both the drum] and the developer smudge roller 12, it is possible to
Only two high friction parts may be provided.

Furthermore, instead of the method in which the photoreceptor 2 is attracted to the drum 1, a photoreceptor drum method in which a photosensitive layer is formed on the surface of the drum itself may be used.

[Effects of the Invention] The image forming apparatus of the present invention transmits rolling force and prevents slippage between the image carrier and the developer smudge roller using the high friction contact portion. As a result, an extremely excellent effect can be achieved in that an image forming apparatus can be provided in which the amount of the image on the image carrier that is peeled off by the developer smudge roller is extremely small.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a rolling force transmission section according to an embodiment of the present invention, Fig. 2 is a block diagram of a wet electrophotographic copying machine, Fig. 3 is a block diagram of a developing device, and Figs. 4 and 5 are It is an explanatory diagram of a conventional example. ]...Drum 2...Photoconductor 12...
・Developer liquid stain roller 16...Rolling force transmission section 21...
・Roller high friction contact member 23...-Knurling processed member

Claims (1)

[Scope of Claims] 1. A developer is applied to an image carrier on which a latent image is formed, and after development, a developer smudge roller is rolled over the image carrier to remove excess developer that has adhered to the image carrier. In the image forming apparatus, a high friction contact portion for preventing slip and transmitting rolling force between the image carrier and the developer smudge roller is arranged other than the latent image recording area of the image carrier and/or An image forming apparatus characterized in that a developer smudge roller is provided in an area other than the aperture area.