JPH03103884A - Electrophotographic recorder - Google Patents

Abstract

PURPOSE:To suppress the occurrence of wear and damage on the surface of a photosensitive body by providing a cleaning member on an electrifying conduc tive member brought into contact with the surface of the photosensitive body. CONSTITUTION:An electrifying device 11 is provided with a cleaning blade 12 and a toner receiver 13. The cleaning blade 12 is to clean the surface of a conductive roller 2, is formed with material such as metal and synthetic resin excellent in cleaning action, and is provided in such a way that its top is brought into contact with the surface of the conductive roller 2. The toner receiver 13 is designed to house the conductive roller 2 in it as well as the cleaning blade 12. Consequently, the surface of the conductive roller 2 is brought contact with that of the photosensitive drum 1 to rotate and electrify the photo sensitive drum 1. Simultaneously the roller removes toner brought into contact with the surface of the drum 1 when a toner image is formed. Thus, the wear and damage on the surface of the photosensitive drum can be suppressed.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Prior Art) An electrophotographic recording device used in a facsimile machine etc. charges the surface of the photosensitive drum with a charging device while rotating the photosensitive drum, and then charges the surface of the photosensitive drum with a charging device. An exposure device forms a latent image on the drum surface, a developing device forms a toner image on the drum surface, a transfer device transfers the toner image on the recording paper, and then a fixing device transfers the toner image to the recording paper. This is to fix the image and record it.

Further, after the transfer, the toner adhering to the surface of the photosensitive drum is removed, and the electric charges on the surface of the photosensitive drum are also removed.

Some electronic recording apparatuses employ a method in which charging is performed by bringing a conductive part into contact with the surface of a photosensitive drum.

In other words, this charging method uses a roller-shaped conductive member as a charging device, and the roller-shaped conductive member is brought into contact with the surface of the photosensitive drum and charges the surface of the photosensitive drum while rotating. The conductive member has a conductive metal surface coated with conductive rubber as an electric W supply layer.

Conventionally, an electrophotographic recording apparatus employing this contact method has adopted the configuration shown in FIG. 2.

That is, numeral 1 in the figure is a photosensitive drum, which is rotated by a rotating device (not shown). Around the photosensitive drum 1, in order from the top in the drawing along the drum rotation direction (direction in the drawing),
A charging conductive roller 2, an exposure device 3, a developing device 4, a transfer device 5, and a fixing device 6 are provided, and a cleaning device 7 and a static eliminator 8 are also provided.

Note that the conductive roller 2 is rotated by a rotation drive device (not shown).

When performing recording, the photosensitive drum 1 is rotated clockwise in the drawing, and the drum surface is sequentially passed through each device disposed around the photosensitive drum 1, and the following operations are performed.

First, when the surface of the photosensitive drum 1 passes through the conductive roller 2, the surface of the photosensitive drum 1 is charged while being in contact with the conductive roller 2. Next, when the surface of the photosensitive drum passes through an exposure device 3, the exposure device 3 exposes the drum surface to light to form an electrostatic latent image representing the original image.

Next, when the surface of the photosensitive drum 1 passes through the developing device 4, the developing device 4 develops the latent image on the drum surface to form a toner image. Next, the surface of the photosensitive drum 1 is transferred to a transfer device 5.
, the transfer device 5 transfers the toner image on the drum surface onto the recording paper P.

The recording paper P is, for example, in the form of a roll, and is sequentially fed out and passed between the photosensitive drum 1 and the transfer device 5 for transfer, and then passed through the fixing device 6 to fix the toner image.

Further, the surface of the photosensitive drum 1 passes through a cleaning device 7. The cleaning device 7 includes a cleaning blade 9, which is a cleaning member that comes into contact with the surface of the photosensitive drum 1, and a toner receiver 10. As the photosensitive drum 1 rotates, a cleaning blade 10 comes into sliding contact with the drum surface and scrapes off toner adhering to the drum surface. The scraped off toner is received and collected by the toner receiver 10.

Next, the surface of the photosensitive drum 1 passes through a static eliminator 8.
! At f, the static eliminator 8 removes the electric charge on the drum surface.

However, in the conventional electrophotographic recording apparatus in which the charging conductive member is brought into contact with each other, the two cleaning members 9 of the cleaner device 7 and the charging conductive roller 2 are placed on the surface of the photosensitive drum 1. The number of members that come into contact with the surface of the photosensitive drum 1 is larger than that of an electrophotographic recording apparatus in which the charging conductive member does not come into contact with the photosensitive drum 1. The occurrence of scratches on the surface and the progress of wear are high, which is one of the causes of shortening the life of the photosensitive drum.

Therefore, as a countermeasure against this problem, the cleaning member 9 is made of a material such as rubber that is less likely to damage the surface of the photosensitive drum.

In this case, there is a problem that the cleaning member 9 cannot sufficiently scrape off the toner from the surface of the photosensitive drum, resulting in a decrease in the cleaning effect.

In addition, in electrophotographic recording devices, it is required to improve the space factor by rationalizing the arrangement structure of members around the photosensitive drum, but it is generally difficult to meet this demand. {( Even in an electrophotographic recording device in which the +4 contacts the photosensitive drum, members arranged around the photosensitive drum cannot be omitted, so it is possible to rationalize the arrangement structure of the parts around the photosensitive drum. It was difficult.

5 (Problem 8 to be Solved by the Invention) As described above, in the conventional electrophotographic recording apparatus, problems regarding the lifespan of the photosensitive drum and the horizontal construction have occurred due to the method of cleaning the photosensitive drum.

The present invention has been made based on the above-mentioned circumstances, and is capable of effectively cleaning the surface of a photosensitive drum while suppressing wear and scratches, and further miniaturizing the structure by rationalizing the arrangement of members around the photosensitive drum. The purpose of the present invention is to provide an electrophotographic recording device that achieves this goal.

[Structure 7 of the Invention (Means for Solving the Problem) In order to solve the above problem, the electrophotographic recording apparatus of the present invention includes a rotating photosensitive drum and a charged conductive material that contacts the surface of the photosensitive drum. The device is characterized by comprising a member and a cleaning member that comes into contact with the charging conductive member.

(Function) With the above configuration, the conductive member contacts the surface of the photosensitive drum to charge the photosensitive drum, and at the same time removes the toner adhering to the drum surface. Conductive part monthly table (from)
ni{-1' 4 without scraping off the 1・ner. Therefore, only the conductive member that also serves as a cleaning member contacts the surface of the photosensitive drum, reducing the number of contact members on the surface of the photosensitive drum and preventing wear and scratches on the drum surface due to contact between members. suppressed.

Furthermore, there is no need to specially provide a cleaning member for cleaning the photosensitive drum around the circumference of the photosensitive drum, and the conductive portions 44 are arranged together in the space of the cleaning device, so that the arrangement of the parts around the photosensitive drum can be improved. is streamlined and can be miniaturized.

Further, since the cleaning member can be formed of a material that can sufficiently scrape off toner adhering to the conductive member without worrying about the material of the conductive member, the cleaning effect can be enhanced.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 shows an example in which the electrophotographic recording device of the present invention is applied to the one shown in Figure 2.
Are the same parts the same as in the diagram? ] Number is attached.

Around the photosensitive drum 1, in order from above in the drum rotation direction (clockwise direction in the figure), there are an exposure device 3, a developing device 4, a transfer device 5, a fixing device 6, and a static eliminator, and between the static eliminator 8 and the exposure device bow. A conductive roller 2 is provided. The conductive roller 2 charges the surface of the photosensitive drum 1 and also has a cleaning action for removing toner adhering to the surface of the photosensitive drum 1. The conductive roller 2 is made of a conductive material with a small coefficient of friction that is sufficient to remove toner. , for example, made of conductive silicone rubber or conductive fluorine rubber. The conductive roller 2 is provided so as to rotate in contact with the surface of the photosensitive drum 1.

In addition, the electrical device 11 includes a cleaning blade 1
2 and a toner receiver 13.

The cleaning blade 12 cleans the surface of the conductive roller 2, and is made of a material with excellent cleaning properties, such as metal or synthetic resin. The cleaning blade 12 is provided with its tip in contact with the surface of the conductive roller 2.

The toner receiver 13 has a case shape that covers the conductive roller 2 and the cleaning blade 12 from above, outside, and below except for the inside facing the photosensitive drum 1, and prevents contact between the photosensitive drum 1 and the conductive roller 2. The toner attached to the photosensitive drum 1 falling from the contact portion of the conductive roller 2 and the cleaning blade 12 is received. That is, the conductive roller 2 and the cleaning blade 12 are housed inside the toner receiver 13 to form a compact structure.

As shown in FIG. 2, the toner receiver used in the cleaning device of a conventional electrophotographic recording apparatus has a case shape that covers the upper, outer, and lower parts of the contact area between the cleaning member and the photosensitive drum. In this embodiment, the conductive roller 2 is housed in nine spaces inside the toner receiver 13. That is, the conductive roller 2 is housed inside the charging device 11 by utilizing the internal space of the charging device 11 .

The operation of the electrophotographic recording apparatus configured as described above will be explained.

During recording, the photosensitive drum 1 is simultaneously rotated clockwise in the drawing.

First, the conductive roller 2 provided in the charging device 11 rotates while contacting the surface of the photosensitive drum 1, thereby charging the surface of the photosensitive drum 1.

Next, the exposure device 3 exposes the surface of the photosensitive drum 1 to form a latent image, and then the developing device 4 performs development to form a toner image on the surface of the photosensitive drum 1.

Transfer device 5 transfers the toner image on the surface of photosensitive drum 1 to recording paper P.
Then, the image transferred to the recording paper P is fixed by the fixing device 6.

Further, the surface of the photosensitive drum 1 reaches the static eliminator 8, and the electric charge is removed by the static eliminator 8. After that, photosensitive drum 1
The surface of 10 reaches the conductive roller 2 provided in the charging device 11 again.

Here, the conductive roller 2 charges the photosensitive drum 1 by rotating with its surface in contact with the surface of the photosensitive drum 1, and also functions to remove toner that has come into contact with the drum surface when forming a toner image.

The conductive roller 2 can remove toner attached to the surface of the photosensitive drum 1 by rotating the conductive roller 2 in the same direction as the photosensitive drum 1 at different rotational speeds, or by rotating the conductive roller 2 in the same direction as the photosensitive drum 1. However, there are methods such as rotating it in a different rotation direction. Since the conductive roller 2 is made of a material sufficient to remove toner, the conductive roller 2 can accurately remove toner from the surface of the photosensitive drum 19. Further, by making the surface of the conductive roller 2 rough, toner on the surface of the photosensitive drum 1 can be removed more reliably.

A portion of the toner removed from the surface of the photosensitive drum 1 falls and is received by a toner receiver 13 of the charging device 11, and a portion of the toner adheres to the surface of the photosensitive drum 1.

Since the cleaning blade 12 is in contact with the conductive roller 2, as the conductive roller 2 rotates, the cleaning blade 12 slides on the surface of the conductive roller 2 and adheres to the surface of the conductive roller 2. Make sure to scrape off any remaining toner. Since the cleaning blade 12 is made of metal, synthetic resin, or the like, it is possible to reliably scrape off toner from the surface of the conductive roller 2.

The toner scraped off from the conductive roller 2 by the cleaning blade 12 is received by the toner receiver 12.

As the cleaning blade 12 constantly cleans the surface of the conductive roller 2 in this way, the conductive roller 2 can charge the photosensitive drum 1 well and can clean the photosensitive drum 1 well.

In this embodiment, the conductive roller 2 applies electric current to the photosensitive drum 1 and also performs cleaning, so there is no need to bring a dedicated cleaning blade into contact with the photosensitive drum as in the conventional case. The number of members that come into contact with the surface of the photosensitive drum 1 is reduced, and the occurrence of scratches and progress of wear on the surface of the photosensitive drum 1 can be suppressed.

The conductive roller 2 is provided in a space of the charging device 11 in order to make contact with the cleaning blade 12 , and the conductive roller 2 is placed around the photosensitive drum 1 .
There is no need to secure a special space for arranging the device, and the device can be made smaller by that space.

Further, in this embodiment, since the conductive roller 2 is used as a cleaning member for the photosensitive drum, the conductive roller 2 can be easily adjusted to an appropriate position for cleaning. Appropriately adjusting the position and pressure of the cleaning member relative to the photosensitive drum 1 is very important in improving the cleaning effect of the cleaning member, but this adjustment has been extremely difficult with conventional cleaning blades.

Note that the charging conductive member that also serves as the cleaning part 1 3 material that is brought into contact with the photosensitive drum is not limited to the conductive roller of the above-described embodiment, but may be formed into an endless band shape and come into contact with the surface of the photosensitive drum while rotating. You may also choose to do so.

Alternatively, it may be configured in a shoe shape so as to come into sliding contact with the surface of the photosensitive drum 1. The cleaning member that contacts the conductive member is also not limited to the configuration of the embodiment.

[Effects of the Invention] As explained above, according to the electrophotographic recording of the present invention, the surface of the photosensitive drum is cleaned by the charging conductive member that comes into contact with the surface of the photosensitive drum, and the surface of this conductive member is also cleaned. Since the cleaning is done with a member, the surface of the photosensitive drum can be cleaned well, and
By reducing the number of members that come into contact with the surface of the photosensitive drum, scratches and abrasion on the surface of the photosensitive drum can be suppressed and the life of the photosensitive drum can be increased. Also, conductive members and cleaning members for universal electricity around the photosensitive drum can be used. By rationalizing the arrangement structure and miniaturizing the charging conductive member, the cleaning member can be made of a material with good cleaning effect without worrying about the quality of the conductive member, and the conductive member for charging can be made to have a good performance. Can be cleaned.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of an electrophotographic recording apparatus of the present invention, and FIG. 2 is an explanatory diagram showing a conventional electrophotographic recording apparatus. 1... Photosensitive drum, 2... Conductive roller, 11...
・Charging device, 12...Cleaning unit, 13...
Toner receiver.

Claims (1)

[Claims] An electrophotographic recording apparatus comprising: a rotating photosensitive drum; a charging conductive member that contacts the surface of the photosensitive drum; and a cleaning member that contacts the charging conductive member.