JP2002006575A - Color image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color image forming device, capable of coping with limited installation space by improving layout, and recovering toner with high efficiency as well as reducing the toner scattering to a minimum at cleaning time. SOLUTION: This color image forming device has plural image-forming means incorporating image carriers arrayed vertically, close to a moving surface of an intermediate transfer belt which is arranged longitudinally, and arranging cleaning means on an area opposite to the lowest part of each of the image carriers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color copying machine or a color printer for forming an image by an electrophotographic system (in which a toner image formed on an image carrier is transferred onto a transfer material such as paper). And a color image forming apparatus.

[0002]

2. Description of the Related Art A drum-shaped photoreceptor, charging means for uniformly charging the photoreceptor surface, laser writing means for exposing the photoreceptor surface based on image data, and
Image forming means including developing means for visualizing an electrostatic charge pattern formed by the laser writing is provided for each of yellow (Y), magenta (M), cyan (C) and black (K). At the same time, the toner images formed on the photoreceptor for each color are sequentially superimposed on the intermediate transfer belt to form a color image (sometimes referred to as a color toner image) on the intermediate transfer belt. Transfer material for color toner images such as paper (hereinafter referred to as paper)
A color image forming apparatus having a configuration in which the color toner image is transferred (transferred) upward and the color toner image is fixed on the sheet by an appropriate fixing unit is well known.

Further, in the above configuration, the toner remaining on the photoreceptor after the transfer of the toner image is cleaned by cleaning means.

The above-described color image forming apparatus is a multi-rotation type that forms a color image by rotating a single photosensitive member a number of times corresponding to, for example, the above-described Y, M, C, and K image formation. One intermediate transfer belt compared to a color image forming apparatus
Since a color image is formed during the rotation, and the color image can be collectively transferred to a sheet, rapid image formation can be realized.

[0005]

However, as described above, for example, a plurality of sets of image forming means having the same configuration are required, so that there is a problem that the apparatus becomes large.

Further, since the above configuration has a plurality of photoconductors, it is more likely that toner scattering will occur than in the multi-rotation type color image forming apparatus.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to reduce the installation space by improving the layout, and to efficiently collect and scatter toner during cleaning. An object of the present invention is to provide a color image forming apparatus which can be reduced.

[0008]

The object of the present invention can be achieved by the following constitution.

(1) A plurality of image forming means including image carriers are vertically arranged adjacent to the moving surface of the vertically arranged intermediate transfer belt and opposed to the lowermost portions of the respective image carriers. A color image forming apparatus, wherein a cleaning unit is disposed in the area where the cleaning is performed.

(2) A plurality of image forming means including an image carrier are vertically arranged close to the moving surface of the vertically arranged intermediate transfer belt, and are opposed to the lowermost portions of the respective image carriers. A color image forming apparatus, wherein a cleaning means is disposed in a region defined by the cleaning means, and a toner collecting container is provided below the cleaning means disposed at the lowermost position.

(3) A paper storage section is provided at a lower portion of the apparatus main body, and an intermediate transfer belt vertically disposed above the paper storage section and an image carrier are provided in proximity to a moving surface of the intermediate transfer belt. A color image forming apparatus comprising: a plurality of image forming means including a plurality of image forming means arranged in a vertical direction, and a cleaning means arranged in a region opposed to a lowermost portion of each of the image carriers.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram for explaining the internal structure of the digital color image forming apparatus. The digital color image forming apparatus (hereinafter, simply referred to as an image forming apparatus) 1
A paper storage unit 20 is provided at a lower portion of the apparatus main body, and an image forming unit 40 and an intermediate transfer belt 60 are provided above the paper storage unit 20.
In addition, the scanner unit 80 is disposed above the apparatus main body.

In the paper storage unit 20, drawable cassettes 201, 202 and 2 provided in three stages in the vertical direction are provided.
A cassette 03 is provided, and these cassettes integrally have appropriate paper feeding means (not shown) including a paper feeding roller.

The image forming section 40 includes Y, M, C, K
The four sets of image forming means 400Y, 400M, 400C and 400K for forming the toner image of each color are linearly arranged in this order from top to bottom.

The mechanical structure of each of the image forming means is the same, and for convenience, only the upper and lower two sets of image forming means 400Y and 400K are denoted by reference numerals in the drawings.

Incidentally, the image forming means 400Y includes an image carrier 410 (in the embodiment, formed of a drum-shaped photoconductor, hereinafter referred to as a photoconductor) which rotates counterclockwise as indicated by an arrow, A scorotron charger 420, a laser writing unit 430, and a developing unit 440 are provided around the 410 and provided in the rotation direction.

Reference numeral 450 denotes the photosensitive member 4
A cleaning member 455 including a blade provided in a counter direction with respect to the rotation direction of the cleaning device 10 and a cleaning unit (cleaning device) including an outer frame of the container (shape).

The cleaning means 450 is disposed so as to include a region opposed to the lowermost portion of each of the photosensitive members 410.

In the cleaning means 450, the cleaning member 455 prevents the toner scraped off from the surface of the photoreceptor 410 from being scattered after the transfer, for example, by removing the outer frame facing the photoreceptor surface. It is desirable to arrange one surface as close as possible to the photoconductor.

The above-described configuration in which the cleaning means 450 is disposed opposite to the lowermost portion of the photosensitive member 410 is more convenient for causing the scraped toner to drop by gravity than when the cleaning means is disposed in a position other than the lowermost position. A good opening can be prepared on the surface of the photoreceptor, so that toner can be efficiently collected and the effect of suppressing toner scattering without adding any special means can be obtained.

Further, a conveying means such as a screw is provided in each of the cleaning means 450, and the collected toner is collected at one place in the front and back direction in the figure, and is provided so as to communicate therewith through a hole. The inside of the pipe is dropped by gravity, or a screw or the like is built in, and sequentially conveyed downward, and the cleaning unit 450 disposed at the lowermost position (in the drawing, the photosensitive member 410 of one element constituting the image forming unit 400K) (Provided at the lower part), the toner can be collected in a toner collection container 457 detachably installed below.
Since the length of the cleaning unit in the vertical direction can be reduced, and the number of the cleaning units is four, an effect of considerably reducing the length in the vertical direction of the image forming unit can be expected.

The intermediate transfer belt 60 is endless,
Has an appropriate volume resistivity, for example, knitted polyimide, thermosetting polyimide, ethylene tetrafluoroethylene copolymer, polyvinylidene fluoride, outside the semiconductive film substrate in which a conductive material is dispersed in engineering plastics such as nylon alloy And two layers coated with fluorine.

In addition, a belt having a structure in which a conductive material is dispersed in silicon rubber or urethane rubber or the like can be used.

The transfer belt 60 is disposed vertically long, and the transfer belt 60 and the photoconductor 410 have a part of the circumference of the photoconductor 410 close to a linear belt moving surface 600. Have a relationship.

The transfer electrodes 605 are disposed so as to face the respective photoconductors 410 with the belt moving surface 600 interposed therebetween.

Reference numerals 650, 660, 670,
Reference numeral 680 denotes a support roller for stretching the transfer belt 60. The support roller may include a tension roller and the like as necessary, and may have an appropriate configuration.

As described above, the configuration in which the intermediate transfer belt 60 is provided in a vertically long manner produces an effect that the installation space (installation floor area) of the apparatus can be reduced.

In other words, when the configuration in which the intermediate transfer belt 60 is arranged horizontally is adopted, at least the length of the intermediate transfer belt (in the figure, the length from the support roller 650 to the support roller 660 is substantially equal to the length of the intermediate transfer belt 60). (Equivalent), the width of the main body of the apparatus is necessary. However, in the case of a vertically long length, the width corresponding to the interval between the belts running in parallel in the figure is a dimension obtained by adding the width of the photosensitive member, the developing means, and the like. The projection area (synonymous with the installation floor area) of the latter can be made smaller than that of the former.

The scanner section 80 has, for example, the configuration shown in FIG. FIG. 2 is a schematic diagram showing a configuration of document reading.

In the figure, an automatic document feeder (hereinafter referred to as A
A document 90 fed using the DF 810 is sequentially imaged on an image sensor (CCD line sensor) 830 via an optical system provided below the roller 910, and the image is stored in the control unit 840. The information is temporarily stored in the provided memory.

The optical system includes a document irradiation lamp 850,
First mirror 85 for deflecting the reflected light from the original 90
3. Includes a second mirror 854, a third mirror 855, and an imaging lens 857 for re-deflecting the reflected light from the first mirror.

The image information read into the memory is subjected to image processing, and an image is written on the photoconductor 410 by the laser writing means 430 in accordance with the resulting image data.

In the above description, the contents of the image processing, the configuration including the ADF 810 of the scanner unit 80, and the like are basically known in the same manner as the configuration of the developing unit and the bias control described with reference to FIG. There is no detailed explanation for it.

Referring back to FIG. 1, reference numeral 30 denotes a heating roller type fixing device, which includes a fixing roller 310 having a built-in heating source, and a pressure roller 320 which rotates while being pressed against the fixing roller.

Reference numeral 50 is a manual feed tray, 70 is a paper discharge tray, and R1 to R7 are transport rollers for transporting the paper fed from the cassette 201 (202, 203) with the recording operation. Alternatively, it is a pair of transport rollers (hereinafter, referred to as transport rollers).

The transport roller R4 also has a paper transport function. However, the transport roller R4 comes into pressure contact with the support roller 660 with the intermediate transfer belt 60 interposed therebetween to transfer a color image formed on the intermediate transfer belt to the paper. Although it functions as a transfer unit, although not shown, a predetermined voltage of a predetermined polarity is applied, and the surface is covered with an electrically insulating feed.

Image formation in the image forming apparatus 1 having the above configuration is roughly as follows. In the description, a single-sided copy of a document is taken as an example.

When the original 90 is fed by the operation of the ADF 810, the original image is illuminated by an original illuminating lamp 850, and the reflected light thereof is reflected by a first mirror 853 and a second mirror 85.
4. After being guided to the image sensor 830 via the third mirror 855 and the imaging lens 857, the image data is temporarily stored in a memory in the control unit 840, and then subjected to image processing.

On the other hand, the surface of each photoconductor 410 rotating in a predetermined direction (counterclockwise) at the start of the image forming process is uniformly charged to the same polarity as the toner by the action of the scorotron charger 420. After that, the image data subjected to the image processing is read out by the control unit 840, and the exposure based on the image data is performed in the form of a writing process of the laser writing unit 430.

The pattern (electrostatic latent image) formed by the writing process is converted into a toner image by a non-contact reversal developing process by a developing unit 440, and then the transfer electrode 60
5 at the same speed as the photoconductor 410,
The image is transferred onto the intermediate transfer belt 60 running in the same direction at a point close to the photoconductor.

The above image formation is performed by image forming means for each color of Y, M, C and K. For example, in the yellow (Y) image forming unit 400Y, writing is performed by a laser writing unit according to an electric signal corresponding to yellow image data, and development is performed using yellow toner.

The toner images visualized by the respective color toners are a yellow toner image, a magenta toner image,
A cyan toner image and a black toner image are superimposed on the intermediate transfer belt in this order to form a color toner image.

The color toner image is transferred onto a sheet conveyed in a timely manner by the action of the transfer roller R4 as a transfer means, and is fixed on the sheet by a heating and pressing action by the fixing means 30. The paper is discharged to the paper discharge tray 70.

The image forming apparatus in the above description includes a printer used on a network in addition to a digital color copying machine used in a stand-alone manner.

[0046]

By improving the layout inside the image forming apparatus, it is possible to reduce the installation space of the apparatus itself, in other words, the installation space of the apparatus, and to efficiently collect toner and reduce toner scattering by utilizing gravity. A useful image forming apparatus was obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining an internal configuration of a digital color image forming apparatus.

FIG. 2 is a schematic diagram illustrating a configuration of document reading.

[Explanation of symbols]

 1 Digital Color Image Forming Apparatus 20 Paper Storage Unit 40 Image Forming Unit 60 Intermediate Transfer Belt 80 Scanner Unit 410 Image Carrier (Photoconductor) 450 Cleaning Unit 455 Cleaning Member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masakazu Fukuchi 2970, Ishikawacho, Hachioji-shi, Tokyo Konica Co., Ltd. (72) Inventor Kosuke Minoshima 1st Sakuracho, Hino-shi, Tokyo In-house Konica Co., Ltd. (72) Invention Person Masahiro Shigetomi 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H030 AA06 AB02 AD03 BB42 BB46 BB53 2H034 BF00 CA04

Claims (7)

[Claims] A plurality of image forming means including an image carrier are vertically arranged adjacent to a moving surface of an intermediate transfer belt disposed in a vertically long manner, and each of the plurality of image forming means is opposed to a lowermost portion of each of the image carriers. A color image forming apparatus, wherein a cleaning unit is disposed in an area. 2. A plurality of image forming means including an image carrier are vertically arranged close to a moving surface of a vertically arranged intermediate transfer belt and opposed to the lowermost portion of each of the image carriers. A cleaning means is arranged in the area,
A color image forming apparatus comprising a toner collection container provided below a cleaning means disposed at a lowermost position. 3. The color image forming apparatus according to claim 1, wherein the image bearing member is a drum-shaped photosensitive member. 4. The image bearing member is a drum-shaped photosensitive member,
The color image forming apparatus according to claim 1, wherein a surface of the intermediate transfer belt facing the drum-shaped photoconductor moves downward from above. 5. An apparatus according to claim 1, further comprising a paper storage portion provided at a lower portion of the apparatus main body, and including an intermediate transfer belt disposed vertically above said paper storage portion and an image carrier in proximity to a moving surface of said intermediate transfer belt. A color image forming apparatus comprising: a plurality of image forming units arranged in a vertical direction; and a cleaning unit arranged in a region opposed to a lowermost portion of each of the image carriers. 6. The color image forming apparatus according to claim 5, wherein said image bearing member is a drum-shaped photosensitive member. 7. The image bearing member is a drum-shaped photosensitive member,
6. The color image forming apparatus according to claim 5, wherein the surface of the intermediate transfer belt facing the drum-shaped photoreceptor moves downward from above.