JPH0562341B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrophotographic copying apparatus using a photoreceptor sheet of an organic photoconductor.

Conventional Structure and Problems Generally, in an electrophotographic copying apparatus using an organic photoconductor photoconductor, as shown in FIG. and the photoconductor driven roll 51b to run,
The photoconductor 51 is charged by the charging charger 52, and the document table 54 is charged by the exposure device 53 having an exposure lamp 53a and an optical fiber lens 53b.
A light image from the photoreceptor 51 is formed as an electrostatic latent image on the photoreceptor 51, and is developed into a visible image by the developer 55.
Next, the copy paper 57 is fed from the copy paper cassette 56 by the paper feed roll 58, and the copy paper 57 is conveyed onto the toner image on the photoreceptor 51 by the transport roll pair 59 and the transfer guide 60, and is then statically transferred. The toner image is transferred onto the copy paper 57 by the transfer charger 61 by electrostatic adsorption. As the photoreceptor 51 and the copy paper 57 further advance, the separation claw 62 separates the copy paper 57 from the photoreceptor 51 and the copy paper 57 is placed on the fixing guide 63.
is guided, the toner image on the copy paper 57 is fixed by the fixing device 64, and the toner image is discharged onto the paper discharge tray 65. As the photoreceptor 51 further advances, the residual toner after the transfer is removed by a cleaning device 66 having a cleaning plate 66a, and the residual charge on the photoreceptor 51 is removed by a discharge lamp 67 to complete the copying process.

With the configuration of the electrophotographic copying apparatus as described above, it is necessary to fuse and connect the ends of the photoreceptor sheet to form an endless belt. In addition, if the circumference of the belt-shaped photoreceptor is not uniform, it will meander as it travels, reducing accuracy in various processes such as charging, exposure, development, and transfer, resulting in only low-quality copied images. There are no drawbacks. Furthermore, when an endless belt-shaped photoconductor is used, burrs are always generated at the fusion spliced parts, so the burrs and the cleaning blade rub against each other violently during cleaning, resulting in the cleaning blade being damaged and the photoconductor being poorly cleaned. There was a drawback. In addition, when trying to obtain a large number of copies, the endless belt-like photoreceptor is run as many times as the desired number of copies, and the processes of charging, exposing, developing, transferring, cleaning, and eliminating static electricity are repeated each time, which increases the copying time. is inefficient.
Further, by repeating the above steps, the photoreceptor deteriorates significantly and must be replaced frequently, and the belt-like shape of the photoreceptor makes it difficult to handle during maintenance and inspection.

OBJECTS OF THE INVENTION An object of the present invention is to provide an electrophotographic apparatus that uses a photoreceptor sheet of an organic photoconductor and can stably obtain high-quality images.

Structure of the Invention The electrophotographic copying apparatus of the present invention sequentially takes out each of the photoconductor sheets from a photoconductor cassette having a plurality of photoconductor sheets, and forms a light image from a document as an electrostatic latent image on each of the photoconductor sheets. A developing roll is arranged to face the developing sleeve of the developing device, and when the photosensitive sheet passes between the developing sleeve and the developing roll, the developing sleeve and the photosensitive sheet are separated by the developing roll. By controlling the gap between the photoreceptor sheet and developing the photoreceptor sheet, there is no need to fusion splice the ends of the photoreceptor sheet to form an endless belt-like photoreceptor, making it possible to remove burrs at the joints. This eliminates the possibility of damage to the cleaning blade, extends the life of the blade, and prevents meandering of the photoreceptor, making it possible to stably obtain high-quality copied images and making efficient use of the photoreceptor sheet. By doing so, the copying time for making multiple copies can be shortened, and since the photoreceptor is stored in the cassette, the photoreceptor can be easily replaced during maintenance and inspection.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 shows a side view of essential parts of an electrophotographic copying apparatus according to an embodiment of the present invention.

In FIG. 2, 1 is the main body of the electrophotographic copying apparatus, 2
3 is a document table cover, 4 is a photoreceptor cassette, and has the following components. Reference numerals 5, 6, and 7 are photoreceptor sheets (hereinafter referred to as photoreceptors) each made of a separated organic photoconductor. 5a and 5b are a pair of transport rolls for the photoreceptor 5, 6a and 6b are a pair of transport rolls for the photoreceptor 6, 7a and 7b are a pair of transport rolls for the photoreceptor 7, and 8 is a control for improving charging and exposure accuracy. It's a belt. 9 is an electrostatic charger, and 10 is an exposure device having an exposure lamp 10a and an optical fiber lens 10b.The electrostatic charger 9 and the exposure device 10 are integrated.

Initially, upon copy start, the photosensitive belt 5 is transported by a pair of transport rolls 5a and 5b, charging is started by the charging charger 9, and the document table 2 and the photoreceptor 5 move at the same speed in the direction of the arrow in the figure. Then, the light from the exposure lamp 10a of the exposure device 10 is reflected from the surface of the document and forms an electrostatic latent image on the photoreceptor 5 through the optical fiber lens 10b.

Next, while forming an electrostatic latent image on the photoreceptor 5, it is supplied to the developing unit 13 by a pair of feed rolls 11, and is conveyed by a pair of developer transport rolls 12a and 12b. By the way, when the leading end of the photoreceptor 5 is held between the pair of developer transport rolls 12b, the developer roll 14 facing the developer 13 is driven to push the back surface of the photoreceptor 5, and the developer The gap between the developing sleeve 13a of No. 17 and the photoreceptor 5 is controlled to realize a developing state, and a visible image is formed with toner.

Next, when the photoreceptor 5 on which the toner image has been formed reaches the transfer charger 15 and the transfer roll 16, the copy paper 1 is transferred from the paper feed cassette 17 at the same timing.
8 supplies the copy paper 18 onto the toner image on the photoreceptor 5 by a paper feed roll 19 and a pair of transport rolls 20a and 20b, transfers the toner image by the transfer charger 15, and at the same time copies the toner image onto the photoreceptor 5. The copy paper 18 is separated from the photoreceptor 5 by a separation belt 21 disposed between the papers 18, and is separated from the fixing guide 24 by a conveyance guide 22 and a conveyance belt 23.
The copy image is guided to a paper output tray 26, fixed by a fixing device 25, and then discharged onto a paper discharge tray 26. After the transfer, the photoreceptor 5 further advances, the residual toner is removed by a cleaning device 27, the residual charge is eliminated by a static elimination lamp 28, and the photoreceptor 5 is transported by a pair of transport rolls 29, 30 to a photoreceptor return device 31, 32. As a result, the photoreceptor 4 is returned to its original position in the photoreceptor cassette 4 and is held between the pair of transport rolls 5a and 5b, completing the copying operation.

The above explanation describes the copying operation when the number of copies is one, but in the case of making multiple copies, the same copying process as explained above is repeated, and the copying operation is performed first by copying the first copy. The photoreceptor 5 is transported to form an electrostatic latent image, and at the same time as the development is completed by the developing device 13, the photoreceptor 6 starts to be transported for copying a second sheet. Also, at the same time as the photoconductor 6 completes development, the photoconductor 3
The photoreceptor 7 has started to be conveyed for copying the first sheet.

The photoreceptor 6 and the photoreceptor 7 transported as described above undergo the same copying process as the photoreceptor 5. Further, the three photoreceptors 5, 6, and 7 are sequentially taken out from the photoreceptor cassette 4 until a predetermined number of copies are completed, and the operation of returning to the photoreceptor cassette 4 again through each copying process is repeated. It is.

Effects of the Invention As is clear from the above description, the electrophotographic copying apparatus of the present invention sequentially takes out the photoreceptor sheets from a photoreceptor cassette having a plurality of photoreceptor sheets, and transfers the optical image from the document onto the photoreceptor sheets. A developing roll is disposed so as to face the developing sleeve of the developing device, and when the photoreceptor sheet passes between the developing sleeve and the developing roll, an electrostatic latent image is formed on the developing roll. By controlling the gap between the developing sleeve and the photoreceptor sheet for development, there is no need to fusion-splice the ends of the photoreceptor sheet to form an endless belt-like photoreceptor. Therefore, burrs can be removed from the connection part, the cleaning blade will not be damaged, the life of the blade will be extended, and high-quality copied images can be stably obtained since meandering of the photoreceptor does not occur. By using the photoreceptor sheet efficiently, the copying time for multiple copies can be shortened, and since the photoreceptor is stored in a cassette, it is easy to replace the photoreceptor during maintenance and inspection. It is something that can be done.

[Brief explanation of the drawing]

FIG. 1 is a side view of essential parts of an example of a conventional electrophotographic copying apparatus, and FIG. 2 is a side view of essential parts of an electrophotographic copying apparatus according to an embodiment of the present invention. 1...Electrophotographic copying device main body, 2...Document stand,
3...Document table cover, 4...Photoconductor cassette,
5, 6, 7... Photoreceptor sheet, 5a, 5b, 6
a, 6b, 7a, 7b... photoreceptor transport roll pair,
8... Control belt, 9... Electrostatic charger, 1
0... Exposure device, 11... Feeding roll pair, 1
2a, 12b...Developer transport roll pair, 13...
Developing device, 14...Developing roll, 15...Transfer charger, 16...Transfer roller, 17...Paper feed cassette, 18...Copy paper, 19...Paper feed roll,
20a, 20b, 30... Conveyance roll pair, 21...
... Separation belt, 22 ... Conveyance guide, 23 ... Conveyance belt, 24 ... Fixing guide, 25 ... Fixing device, 26 ... Paper output tray, 27 ... Cleaning device, 28 ... Static elimination lamp, 31, 32 ...Photoconductor return control device.

Claims (1)

[Claims] 1. Take out each of the photoreceptor sheets one after another from a photoreceptor cassette having a plurality of photoreceptor sheets, form a light image from the document as an electrostatic latent image on each of the photoreceptor sheets, and place the photoreceptor sheets facing a developing sleeve of a developing device. A developing roll is arranged so that when the photosensitive sheet passes between the developing sleeve and the developing roll, the developing roll controls the gap between the developing sleeve and the photosensitive sheet to perform development. An electrophotographic copying device configured as follows.