JPH0443374A - Color image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a method for sequentially transferring toner images formed by toner particles of different colors on a latent image carrier such as a photoreceptor or an insulator onto an intermediate transfer member. The present invention relates to a color image forming apparatus that forms a composite image (color image) and finally transfers this composite image to a transfer material.

(Prior Art) In recent years, transfer-type color image forming apparatuses have been developed to sequentially form toner images of different colors on a layered image carrier such as a photoreceptor or an insulator, and to transfer each toner image multiple times onto a transfer material. This method has come to be used.

For example, Japanese Patent Application Laid-Open No. 55-90972 discloses that as a transfer method, a toner image of three or four colors such as yellow, cyan, magenta, and black formed on a latent image carrier is transferred to an intermediate layer as compared to the following. A color image forming apparatus employs a method in which a composite image is formed by overlapping images on an intermediate transfer member on a drum or belt, which is an image carrier, and the composite image is transferred all at once from the intermediate transfer member to a transfer material. Proposed.

A conventional color image forming apparatus will be described below with reference to the drawings.

FIG. 4 is a side view of a conventional color image forming apparatus. In FIG. 4, reference numeral 1 denotes a photoreceptor having a photoconductive layer on its surface, which rotates in the direction of arrow a. Around the photoreceptor 1, there is a charger 7 for uniformly charging the photoreceptor, a laser scanner for writing to form an electrostatic latent image on the photoreceptor, and L.
The optical system 4 as an exposure means such as an ED head, the developing machines 3a to 3d as developing means for visualizing an electrostatic latent image, and the rotational direction of the photoreceptor from the position where the photoreceptor l and the intermediate transfer member 2 are in contact with each other. A cleaning device 6 is arranged on the downstream side. The developing units 38 to 3d contain toner of each color of yellow, magenta, cyan, and black, and are provided so as to be able to approach and separate from the photoreceptor 1 in the directions of arrows A and b'.

The photoreceptor 1 is in contact with an intermediate transfer member 2 serving as an intermediate transfer means that rotates in the direction of arrow C on the downstream side of the developing device 3a with respect to the rotation direction. The intermediate transfer body 2 is made by dispersing a substance such as carbon in resin, and has a resistance value of 10'Ωcm to 101ffi.
It is made of material controlled to Ωcm.

A cleaning device 9 is disposed so as to be able to approach and separate from the intermediate transfer body 2 in the directions of arrows d and d', and is used to clean residual toner on the intermediate transfer body. It consists of magnetic brushes, conductive brushes, etc.

Reference numeral 11 denotes an intermediate transfer device for transferring toner from the photoconductor 1 to the intermediate transfer body 2, which includes a corona discharger to which a high voltage is applied, a metal roller, and a conductive device to which carbon, etc. is dispersed in a resin and a high voltage is applied. It is composed of a roller and is disposed inside the intermediate transfer body at a position where the intermediate transfer body 2 and the photoreceptor 1 are in contact with each other.

Reference numeral 5 denotes a transfer material 13 that moves in the direction of the arrow e, which is also the intermediate transfer body 2.
A transfer device for transferring the toner, 8 a registration roller that aligns the timing of the transfer material 13 with the composite image on the intermediate transfer body 2 and conveys the transfer material 13, 10 fixes the toner on the transfer material to the transfer material A fixing device 12 is a transfer material cassette that stores transfer materials.

Regarding the color image forming apparatus configured as above,
The operation will be explained below. First, in a dark area, the surface of a photoreceptor having high resistance is uniformly charged by a charger 7 that generates corona ions by corona discharge, and an optical system 4 consisting of a laser scanner or an LED head is used.
By exposing the photoreceptor 1 to light according to image data, an electrostatic latent image is formed on the photoreceptor, which is a photoconductor.

Next, the electrostatic latent image on the photoreceptor 1 is developed with yellow toner from the developing device 3a, thereby obtaining a yellow toner image on the photoreceptor. Next, the yellow toner image is transferred by the intermediate transfer device 11 onto the intermediate transfer body 2 which is in contact with the photoreceptor.

Residual toner that has not been transferred from the photoreceptor 1 to the intermediate transfer member 2 is cleaned by a cleaning device 6, and the surface of the photoreceptor 1 is refreshed. Thereafter, the same steps as described above are repeated for each color component, and toner images of different colors are sequentially superimposed on the intermediate transfer body 2 to obtain a composite image.

The transfer body 13 sent out from the transfer material cassette 12 is aligned with the composite image obtained on the intermediate transfer body 2 by the registration rollers 8, and guided to the transfer section between the intermediate transfer body 2 and the transfer device 5 ( The composite image on the intermediate transfer body 2 is transferred all at once onto the transfer material 13 at the transfer section by the transfer device 5, which is a corona discharger to which a high voltage is applied.The composite image transferred onto the transfer material 13 at once is guided to the fixing device 10, fixed on the transfer material 13 by heat and pressure, and discharged.

The toner of the composite image that has not been completely transferred to the transfer material 13 by the transfer device 5 remains on the intermediate transfer member 2 as residual toner. This residual toner is removed by cleaning device 9 and refreshed. The cleaning device 9 is configured to be able to move toward and away from the intermediate transfer body 2, and is kept at a position apart from the intermediate transfer body 2 until one composite image is obtained, and the resulting composite image is transferred. After the toner is transferred onto the transfer material 13 by the device 5, the toner comes into contact with the toner to clean the remaining toner. When replacing the intermediate transfer body 2, only the intermediate transfer body is individually taken out from the main unit, and the cleaning device 9 is exposed after the intermediate transfer body is taken out.

(Problems to be Solved by the Invention) However, the conventional configuration has the following problems.

1) An intermediate transfer device for transferring toner from a photoreceptor to an intermediate transfer member and a cleaning device for cleaning the intermediate transfer member are separately incorporated into the device, and service maintenance by a service person is frequently required.

2) Since the cleaning device is exposed when replacing the intermediate transfer member, the interior of the device is contaminated by toner scattering.

3) The cleaning device for the intermediate transfer body requires a separation mechanism, and the alignment accuracy of the intermediate transfer body and cleaning device is very important. However, in the conventional configuration, the intermediate transfer body and cleaning device are assembled separately. This makes positioning difficult and causes poor cleaning.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a color image forming apparatus that requires maintenance using a container and can eliminate internal contamination due to toner scattering.

(Means for Solving the Problem) For this purpose, the present invention provides an electrostatic latent image for each color component by individually exposing a uniformly charged latent image carrier to a light image separated into each color component. an exposure means for forming an electrostatic latent image for each component, a developing means for developing the electrostatic latent image of each component with a developer of a different color to form an individual image, and an intermediate image forming means for sequentially converting the developed image on the latent image carrier into an intermediate image. A cartridge including an intermediate transfer member that is superimposed on the transfer member to form a composite image, and a cleaning device that can be brought into and out of contact with the intermediate transfer member and the intermediate transfer member as an integrated unit, and the cartridge is removed from the main device. In addition to the cleaning blade of the cleaning device, the cleaning device also includes a contact member that contacts the intermediate transfer member on the downstream side of the cleaning blade with respect to the rotational direction of the intermediate transfer member.

(Function) In the above configuration, when the intermediate transfer device, which is made into a cartridge as an integrated unit, and the cleaning device that can be brought into and out of contact with the intermediate transfer body are removed from the main device, the rotation direction of the cleaning blade of the cleaning device and the intermediate transfer body is On the other hand, a contact member contacts the intermediate transfer member on the downstream side of the cleaning blade, and when the cartridge is installed in the main unit, the cleaning blade and the contact member are separated from the intermediate transfer member, so that the cleaning blade can be easily removed. Maintenance is possible, and the interior of the machine can be prevented from being contaminated due to toner scattering when replacing the intermediate transfer member.

(Example) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side view showing a schematic configuration of a color image forming apparatus of the present invention, in which 1 is a photoreceptor as a latent image carrier, 2 is an intermediate transfer body, and 3a to 3d are developing means for each color component. 4 is an optical system as an exposure means, 5 is a transfer device,
6 is a cleaning device, 7 is a charger, 8 is a register roller, 9 is a cleaning device, 10 is a fixing device, 11 is an intermediate transfer device, 12 is a transfer material cassette, 13 is a transfer material,
Since these are the same as the conventional device shown in FIG. 4, detailed explanation will be omitted. Reference numeral 15 denotes a cartridge in which the intermediate transfer body 2, the intermediate transfer device 11, and the cleaning device 9 are integrated into one unit. FIG. 2 is a detailed view of the cartridge 15. Reference numeral 16 denotes a cleaning blade made of urethane rubber or the like which is used for cleaning with a magnetic brush or a conductive brush. Reference numeral 18 denotes a lever rotatably supported by the main unit 24 on a rotation shaft 28. One end of this lever 18 engages with one end of the separation lever 23, and the other end is connected to the plunger 29 of the solenoid 20. There is. Reference numeral 14 denotes a spring that biases the separation lever 23 in a direction that brings the cleaning blade 16 into contact with the intermediate transfer body 2, and 19 a spring that urges the lever 18 in a direction that engages the separation lever 23.

Reference numeral 22 denotes an abutting member provided at the end of the separation lever 23 facing the intermediate transfer body 2 on the downstream side of the cleaning device 9 with respect to the rotating direction of the intermediate transfer body 2;
2 is made of an elastic material such as a sheet-like film, rubber, or sponge.

This device has the above-mentioned configuration, and its operation will be explained next.

After uniformly charging the photoreceptor 1, the optical system 4 charges the photoreceptor 1.
is exposed in accordance with the image data to form an electrostatic latent image, this electrostatic latent image is developed to form a toner image, and the operation of transferring this toner image to the intermediate transfer body 2 is repeated for each color component. The color image forming operation of superimposing toner images of different colors on the transfer member 2 to form a composite image and then transferring the composite image to the transfer material 13 all at once is the same as that of the conventional apparatus shown in FIG. 4 above. .

As shown in FIG. 2, the cartridge 15 is
When the solenoid 20 is excited and the lever 18 is rotated in the direction of the arrow g against the spring 19 by the plunger 29 which is attracted in the direction of the arrow f, the separation lever 23 is moved in the direction of the arrow. The cleaning blade 16 is rotated to bring the cleaning blade 16 into contact with the intermediate transfer body 2.

In addition, when the residual toner is not being cleaned, that is, when a composite image is being created on the intermediate transfer member 2, the solenoid is de-energized, so that the cleaning blade 16 and the contact member 22 are removed from the intermediate transfer member 2. 2 and not in contact with the intermediate transfer body 2, the composite image on the intermediate transfer body 2 will not be disturbed.

Furthermore, when the cartridge 15 is removed from the apparatus main body 24, the separation lever 23 is released from the lever 18 and is pulled by the spring 14 and rotates in the direction of arrow h'. comes into contact with the intermediate transfer body 2. As a result, the toner in the cleaning device 9 is transferred to the contact member 22 that contacts the intermediate transfer body 2.
The cleaning blade 16 shuts off the toner from the outside, thereby preventing the toner from scattering to the outside.

FIG. 3 is a side view showing another embodiment of the present invention, in which the cleaning device 9 is provided with a cleaning member 21 such as a magnetic brush or a conductive brush. Abutment members 22 are provided on the upstream and downstream sides of. This abutting member 22 has a portion that comes into contact with the intermediate transfer body 2 such as a sheet-like film, rubber, etc.
It is made of elastic material such as sponge.

The cleaning member 21 such as a magnetic brush or a conductive brush and the contact member 22 are released from the lever 18 when the solenoid 20 is energized when the intermediate transfer cartridge is installed in the apparatus main body 24. When the separation lever 23 rotates in the direction indicated by the arrow h, it comes into contact with the intermediate transfer body 2;
Clean the residual toner on the intermediate transfer body 2.

In addition, when the residual toner is not being cleaned, that is, when a composite image is being created on the intermediate transfer member 2, the solenoid is de-energized and the spring 19 is activated by the arrow g'
The lever 18, which is biased in the direction, moves the separation lever 23 in the direction of the arrow h.
' direction, the cleaning member 21 such as a magnetic brush or a conductive brush, and the contact member 22 are separated from the intermediate transfer body 2, so that the composite image on the intermediate transfer body 2 is not disturbed.

Further, when the cartridge 15 is removed from the main body of the apparatus, the separation lever 23 is released from the lever 18, and the spring 1
4 to rotate in the direction of arrow g, the cleaning member 21 such as a magnetic brush or a conductive brush and the contact member 22 come into contact with the intermediate transfer member 2 . As a result, the toner inside the cleaning device is cut off from the outside, and the toner is prevented from scattering to the outside.

(Effects of the Invention) As explained above, the present invention creates an electrostatic latent image for each color component by individually exposing an optical image separated for each color component onto a latent image carrier charged in a negative manner. an exposure means for forming the electrostatic layer image for each component, a developing means for developing the electrostatic layer image of each component with a developer of a different color to make it into an individual image, and a sequential development means for developing the image on the latent image carrier. An intermediate transfer body that is superimposed on the intermediate transfer body to form a composite image.

A cartridge in which the intermediate transfer body and a cleaning device that can move toward and away from the intermediate transfer body are integrated into one unit, and when the cartridge is removed from the main unit, the rotation direction of the intermediate transfer body together with the cleaning blade of the cleaning device is provided. The cleaning blade is configured with a contact member that contacts the intermediate transfer member on the downstream side of the cleaning blade, making maintenance easy and preventing contamination inside the machine due to toner scattering when replacing the intermediate transfer member. can be done.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a side view showing a schematic configuration of a color image forming apparatus, and Fig. 2 is a side view of a state in which an intermediate transfer body in the form of a cartridge is installed in the main unit. FIG. 3 is a side view of another intermediate transfer member removed from the main unit, and FIG. 4 is a side view of a color image forming apparatus using a conventional intermediate transfer member. l...Latent image carrier, 2...Intermediate transfer body, 38-3d
Developing means, 4 Exposure means, 9 Cleaning device, 15 Cartridge, 16 Cleaning blade, 22 Contact member, 24 Main unit.

Claims (1)

[Scope of Claims] Exposure means for forming an electrostatic latent image for each color component by individually exposing an optical image separated for each color component on a uniformly charged latent image carrier; A developing means for developing the electrostatic latent image of each component with a developer of a different color to form a developed image individually; A cartridge comprising an intermediate transfer body for forming a composite image, and a cleaning device that can be moved into and out of contact with the intermediate transfer body and the intermediate transfer body as an integrated unit; A color image forming apparatus comprising: a cleaning blade and a contact member that contacts the intermediate transfer member downstream of the cleaning blade with respect to the rotational direction of the intermediate transfer member.