JPS5926766A - Developing device of electrophotography - Google Patents

Abstract

PURPOSE:To prevent the deterioration of development characteristics due to the fatigue of a developer, by dipping a squeeze roll and a developing electrode in the developer in a developer tank when the device is not used, and dipping only the development part when used. CONSTITUTION:When the device is not used, there is no developer in a reservoir 30 and the developing part 3 including the squeeze roll 5 and developing electrode 3 is dipped in the developer 11 in the developer tank 10. Therefore, toner components and resin components in the developer 11 never stick to exposed parts of the squeeze roll 5 and developing electrode 4. When the device is in use, a pump 20 is put in operation to send the developer 11 from the developer tank to the reservoir 30. Therefore, the developer 32 is reserved in the reservoir 30 and an overflowing developer is sent to the developing part 3, so the squeeze roll 5 functions with an invariably fresh developer. When the development is completed, the pump 20 is stopped and an original disuse state is entered. Thus, the deterioration of development characteristics is prevented.

Description

[Detailed description of the invention] The present invention relates to an electrophotographic developing device.

In a wet-type electrophotographic apparatus, the exposed recording material is developed in a developing section using a liquid developer (hereinafter referred to as "developer"), and after being fixed, it is delivered to a fixed position on the K7Ji. FIG. 1 shows this situation, in which a recording material 1 exposed in an exposure section (not shown) is sent to a developing section 3 via a feed roller 2, and is passed through a developing electrode 4 in this developing section 3. After being developed, the image is sent to a fixing section via a squeeze roller 5. The image section 3 is provided with a curved guide 6 for guiding the recording material 1 being conveyed, and is immersed in a developer 8 contained in a liquid tank 7. However, in an electrophotographic apparatus, the liquid tank 7 is not filled with liquid, and the low-solvent liquid 8 is not stirred, so the developer in the developing section 3 that develops the recording material 1 is always constant, and the developer becomes fatigued. As a result, the developing characteristics deteriorate, making it impossible to perform clean development.

As an electrophotographic apparatus that overcomes these drawbacks, a developing solution circulation device as shown in FIG. 2, for example, has been proposed. That is, a suction pipe 71 for sucking up the developer from the liquid tank 7 is attached, and a pump 72 is disposed at the top of the suction pipe 71, and the developer sucked up by the pump 72 is discharged into the developing section 3 through a discharge pipe 73. I try to do that. In this case, the developing solution 8 in the liquid tank 7 is circulated and replenished to the upper part of the developing section 3 through the pump 72, the suction pipe 71 and the discharge pipe 73, so that the developing solution 8 in the developing section 3 is The liquid will be fresh at normal pressure. Therefore, according to this device, FIG.
The disadvantages of the device shown in Figure 1 will be eliminated. However, even in this device, the developer that adheres to the photosensitive paper 1 during development adheres to the squeeze roller 5 and the developing electrode 4, and if the device is stopped for a long period of time, it dries and the toner and resin components contained in the developer 8 are removed. The disadvantage is that the toner component or resin component adheres to the squeeze roller 5, and during subsequent development, the toner component or resin component adheres to the photosensitive layer surface of the developed recording material, causing stains, and ultimately making it impossible to perform development smoothly. Therefore, the purpose of this invention is to overcome the above-mentioned drawbacks (・'7
An object of the present invention is to provide a developing device for Bago photographs.

The present invention will be explained below based on an illustrated example of MJ2.

In the developing device of the present invention, as shown in FIG.
a developer tank 30 that includes a developer tank 30, a pump 2o for sucking up the developer 11 from the developer tank 10, and a pump 2o for retaining the developer sucked up by the pump, as well as an overflow filter. A reservoir blade is provided for supplying the developed developer 32 to the developing section 3.The developer tank 1o and the pump are connected by a suction pipe 21, and the bottoms of the pump and the reservoir are connected to a connecting pipe n. In addition, the overflow portion of the developer 32 that has been sucked up into the reservoir 3o by pumping is supplied to the developing section 3 via the discharge pipe 31. The amount of developer retained is as shown in Figure 3 (B) when in use (the squeeze roller is placed above the developer level and the developing area is immersed in the developer, and when not in use it is as shown in Figure 3 (5)). (It is sufficient that the amount is suitable for immersing both the developing section and the squeeze roller under the liquid surface.

In such a structure, when the electrophotographic apparatus is not used, as shown in FIG. The developing section 3 including the pole 4 is immersed in the development process.Therefore, even if it is not used for a long period of time, the adhering developer dries, resulting in low solubility.
The toner components and resin components contained therein will not stick to the squeeze roller 5 or the exposed portion of the developing electrode 4.

When the electrophotographic apparatus is used, the pump is activated to suck up the developer 11 in the developer tank 10 through the suction pipe 21 and send it to the reservoir blade through the connecting pipe η. Therefore, the developer 32 is retained in the reservoir blade as shown in FIG. 3 (I3), and when the pump draws up more developer 21, the overflow is discharged through the discharge pipe 31.
The released developer is then supplied to the developing section 31. In this way, when using the electrophotographic apparatus, the squeeze roller protrudes from the surface of the developer, so it not only functions as a squeeze roller, but also protects the developer 11.
Since W is circulated, new W and retaining liquid are always supplied to the developing section 3, and clean development can be achieved.

When the development is completed in this way and the electrophotographic device is not used, the operation of the pump is stopped, and the developer 32 in the concave reservoir passes through the connection pipe η and the suction pipe 21 to the developer tank. It will be collected on 10th. Therefore, the developer tank 10
By increasing the liquid level of the developer 11 in the Pfi 3
Since the squeeze roller 5 and the developing electrode 4 are immersed so that 1>1(A).

As described above, according to the electrophotographic developing device of the present invention, when not in use, the squeeze opening/-ra and the developing section are immersed in the developer e, the brightness in the tank, and the retaining solution, and when in use, the pump is used to immerse the developer in the developer tank. By sucking up the retained solution into the reservoir, the liquid level in the developer tank j7:3 can be lowered to immerse only the developing area, and development can then be carried out with fresh Bright 1 developer. The toner component and the resin component do not stick to the squeeze roller or the developing electrode 1b, making it possible to perform clean development.

Note that the structure of the developer tank, suction pipe, connecting pipe, reservoir, discharge pipe, etc. in the above-mentioned embodiments may be of any shape (the developer in the developer tank may touch the squeeze roller and the developing electrode when not in use). In addition to being immersed, the developer in the developer tank collapses only the developing section during use, so that a new 'fJ1.
It is sufficient if the structure is such that the developer can be supplied to the developing section.

The electrophotographic imaging device of the present invention is configured such that the squeeze roller is placed above the developer surface when the device is in use, and is positioned below the liquid surface when the device is not in use. There is a characteristic in that.

Therefore, when the apparatus is not in use, the squeeze roller may be moved, for example, so that the squeeze roller is below the surface of the developing solution. It can be used not only in photographic developing devices (for example, it can also be used in silver halide photographic developing devices. In other words, during visual imaging, the squeeze roller is drained from the developer and the development is performed. The roller may be constructed so as to be immersed in the 'fJ1.image i.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views schematically showing the state of the imaging device in a conventional electrophotographic apparatus, and FIGS. 3(A) and α() are electrophotographs according to the present invention. FIG. 5A is a diagram showing a schematic structure of the developing device, in which FIG. 5A shows a state when not in use, and FIG. DESCRIPTION OF SYMBOLS 1... Photosensitive paper, 2... Feed roller, 3... Developing section (, 4...' image electric grip, 5... Squeeze roller, 6...
...Guide, 7, 10...Developer tank, 8, 11,
32... Current liquid, koji, 72... Pump, 30...
・Reservoir. LLt ff, a person agent cheap form)〆h
Three brooms! 82 Diagram J 6 6.4 Figure j

Claims (1)

[Claims] The recording material carrying the latent image is developed by passing through a liquid developer stored in a developer tank, and a squeeze roller disposed above the surface of the liquid developer causes the latent image to be deposited on the recording material. A developing device that squeezes out the liquid distribution agent includes a developer tank including a squeeze roller, a developer electrode, etc., a pump that sucks up the developer in the developer tank, and a developer sucked up by the pump. By storing developer in this reservoir when in use, the liquid level in the developer tank is lowered and the squeeze roller is raised above the liquid level, and when not in use, the developer stored in the reservoir is used for development. An electrophotographic developing device characterized in that the liquid level in the developer tank is raised from the point where the liquid developer is returned to the developer tank, and a squeeze roller is immersed in the liquid developer.