JPS63151967A - Multicolor recorder - Google Patents

Abstract

PURPOSE:To prevent the generation of color mixing and to obtain a multicolor image excellent in its quality by constituting plural developing devices having different colors so as to move them near/far to/from the photosensitive body, and after ending development, moving away respective developing devices fro the photosensitive body. CONSTITUTION:A 1st exposure 29a and a 2nd exposure 29b are simultaneously applied to the photosensitive body 20 and toner images 30, 32 having different colors are formed by 1st and 2nd developing devices 21a, 21b. After development, the 1st and 2nd developing devices 21a, 21b are moved in directions away from the photosensitive body 20 as shown in arrows C1, C2. Thereby, a 1st toner image formed by the 1st developing device 21b is not brought into contact with toner in the 2nd developing device 21b at the time of passing the 2nd developing device 21b by the movement of the photosensitive body 20 in an arrow B direction. Consequently, the structure of developing devices prevented from color mixing in toner images can be obtained in the multicolor recorder provided with plural developing devices having different colors.

Description

[Detailed description of the invention] [Table of contents] - Overview - Field of industrial application - Prior art - Problems to be solved by the invention - Means for solving the problems - Effects - Examples - Effects of the invention [Overview] In order to solve color mixing (mixing of two or more types of toner) in multicolor recording devices using electrophotographic processes,
A multicolor recording device that creates toner images of each color on a photoconductor using multiple developing devices, and then moves each developer away from the photoconductor to prevent the toner image of each color from coming into contact with a developing device of another color. .

[Industrial application field]

The present invention relates to a multicolor recording device using an electrophotographic process, and particularly to an improvement of a developing device for improving print quality. A multicolor recording device is required to produce high-quality images in the same way as a monochrome recording device, but along with this, multicolor recording without color mixture is also required.

[Conventional technology]

The structure of a conventional multicolor recording device is shown in FIG. Around the photosensitive drum 1, an optical static eliminator 2, an initial charger 3, and a first exposure system 4 are installed.
, a first developing device 5, a recharging device 6, a second exposure system 7, a second developing device 8, a transfer device 9, an AC static eliminator 12, and a cleaner 13 are provided. 10 is a recording paper, and 11 is a fixing device.

The photosensitive drum 1 rotates in the direction of arrow A, a latent image is formed by the first exposure system 4, and a toner image 14 of a first color is formed by the first developing device 5. Another latent image is further formed on the photosensitive drum 1 by the second exposure system 7, and this becomes a toner image 15 of a second color by the second magnetic brush developing device 8. Each of the toner images 14 and 15 is transferred onto a recording paper 10 by a transfer device 9 and fixed by a fixing device 11.

[Problems to be Solved by the Invention] In the conventional multicolor recording device, the toner image 14 of the first color formed in the first developer 5 passes through the second developer 8 of a different color. When doing so, there is a problem in that toner of another color comes into contact with the toner of the second developing device 8 and adheres to the toner image of the first color, causing color mixing.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and it is an object of the present invention to provide a developing device structure that prevents color mixing of toner images in a multicolor recording device equipped with a plurality of developing devices of different colors.

[Means for solving problems]

In order to achieve this object, in the present invention, a plurality of developing devices containing toner of different colors are provided around the photoreceptor, and toner images of different colors on the photoreceptor formed by each developer are transferred to another medium. In a multicolor recording device that forms a multicolor image by transferring, each of the developing devices is configured to be movable so as to approach the photoreceptor during development and move away from the photoreceptor after the development is completed.

FIG. 1 shows the principle of the operation process of the multicolor recording apparatus according to the present invention. A first developer 21a and a second developer containing toners of different colors are placed around the photoreceptor 20 moving in the direction of arrow B.
A developing device 21b is provided.

23a and 23b are first and second chargers, 25 is an optical static eliminator, 26 is a cleaner, 27 is an AC static eliminator, and 28 is a transfer drum. Each of the developing devices 21a and 21b is movable in the vertical direction of the figure, and after the development is completed, the respective developing devices 21a and 21b are moved by arrows C, , and C2.
It is configured to move in a direction away from the photoreceptor 20 as shown in FIG.

[For production]

A first exposure 29a and a second exposure 29b are simultaneously performed on the photoreceptor 20, and the first and second developing units 21a and 21b are
Toner images 30 and 32 of different colors are formed. After the development is completed, the first and second developing units 21a.

21b moves in a direction away from the photoreceptor 20 as shown by arrows C, ,C. Therefore, when the first toner image 30 formed in the first developing device 21a passes through the second developing device 21b due to the movement of the photoreceptor 20 in the direction of arrow B, the first toner image 30 formed in the first developing device 21a passes through the second developing device 21b.
It does not come into contact with the toner of 1b.

〔Example〕

FIG. 2 is a block diagram of a color recording apparatus using four color toners according to the present invention. This embodiment has a configuration in which four developing units 22a to 22d containing toners of four colors, black, cyan, magenta, and yellow, are arranged in parallel around the photoreceptor 20. Four chargers 24a to 24d are provided corresponding to each of the developing devices 22a to 22d. Each developer 22
The elements a to 22d are configured to be able to reciprocate toward and away from the photoreceptor 20. Any known suitable movement means can be used as such a reciprocating mechanism. By configuring each developing device 22a to 22d to be movable in this way, each developing device 22a to 22d can be moved to the photoreceptor 22 during development.
The developing units 22a to 22d can be moved in a direction away from the photoreceptor 20 as indicated by arrows D1 to D4 after the development is completed.

The other configurations are the same as the example shown in FIG.

The photoreceptor 20 rotates in the direction of arrow B, and the four chargers 24a
~24d operate simultaneously. Subsequently, four exposure systems 403 to 40d simultaneously irradiate light to form latent images on the photoreceptor 20 in order to form latent images corresponding to images of each color. These latent images are developed by depositing toners of different colors in each of the developing units 22a to 22d. After forming the toner images in this way, each of the developing units 22a to 22d moves to the direction indicated by the arrow D before each toner image reaches the position of the adjacent developing unit.
It moves in the direction away from the photoreceptor 20 as shown in 1 to D4. As a result, the toner image on the photoreceptor 20 passes under each developing device without coming into contact with toner of a different color developing device. The four-color toner images are transferred onto a recording paper (not shown) on the transfer drum 28 while being timed so as to form a predetermined color image on the transfer drum 28.

〔Effect of the invention〕

As explained above, in the multicolor recording apparatus according to the present invention, a plurality of developing devices of different colors are configured to be movable toward and away from the photoreceptor, and after the completion of development, each developer is moved toward and away from the photoreceptor. It is moved in the direction away from. Therefore, the toner image formed by each developing device does not come into contact with toner of a different color from another developing device, thereby preventing color mixing and producing a multicolor image of good quality.

[Brief explanation of the drawing]

FIG. 1 is a principle diagram of the present invention, FIG. 2 is a configuration diagram of an embodiment of the present invention, and FIG. 3 is an explanatory diagram of the prior art. 20...Photoreceptor, 21a, 21b, 22a to 22d・"
Developing device, 2 days...Transfer drum, 30, 32...
Toner statue.

Claims (1)

[Claims] 1. A plurality of developing devices (21a
, 21b) are provided around the photoreceptor (20), and different color toner images (30, 3
In a multicolor recording device that forms a multicolor image by transferring 2) onto another medium, each of the developing devices (21a, 21b) approaches the photoreceptor (20) during development, and closes the photoreceptor (20) after the development is completed. (20) A multicolor recording device characterized in that it is configured to be movable away from. 2. Four developing devices (22a to 22d) containing toners of four colors, yellow, magenta, cyan, and black, are arranged in parallel around the photoreceptor (20). A multicolor recording device according to claim 1.