Electrophotography – Cleaning of imaging surface – Fibrous brush
Reexamination Certificate
1999-03-12
2001-11-06
Brase, Sandra (Department: 2852)
Electrophotography
Cleaning of imaging surface
Fibrous brush
Reexamination Certificate
active
06314266
ABSTRACT:
FIELD OF THE INVENTION AND RELATED ART
The present invention relates to a cleaning apparatus for removing the developer remaining on the image bearing member employed by an electrophotographic image forming apparatus. It also relates to a process cartridge comprising such a cleaning apparatus, and an image forming apparatus in which such a process cartridge is removably installable.
In an image forming apparatus such as a printer, an electrostatic latent image is formed on an image bearing member (electrophotographic photosensitive member) by selectively exposing the image bearing member uniformly charged by a charging device. Then, the electrostatic latent image is developed, that is, visualized, with the use of a developing device and a developer. Then, the image composed of developer is transferred onto a recording medium. The developer remaining on the image bearing member after image transfer is removed by a cleaning blade and a brush roller to prepare the image bearing member for the following image forming rotation so that the image forming process is always carried out with the use of clean portion of the image bearing member. The removed developer is collected into a cleaning container and stored there.
In recent years, it has been made possible to simplify image formation apparatus maintenance with the use of a cartridge. According to this method, an image bearing member, a charging device, a developing device, a cleaning portion, a waste toner bin, and the like are integrated into the form of a cartridge which can be installable into the main assembly of an image forming apparatus by a user so that developer can be easily replenished or the image bearing member can be easily exchanged. Further, an image bearing member has become more durable, and the number of prints each cartridge can produce has also increased, which does not correspond with the limited developer supplying capacity of the developing device. Thus, the idea of making the developing device independent from the other components, that is, making a development cartridge completely independent from a cartridge which comprises the rest of the components, has been put to practical use. In other words, according to this idea, an image forming apparatus employs two different process cartridges: a drum cartridge, as an image formation process cartridge, integrally comprising an image bearing member, a charging device, and a cleaning portion; and a development cartridge comprising a developing device, so that not only can an image forming apparatus be easily maintained, but also two different cassettes can be replaced independently from each other according to the durability of the aforementioned main components. The waste toner, resulting from the cleaning of the photosensitive drum in a drum cartridge, is stored in the waste toner bin of the drum cartridge with a capacity large enough to store all the waste toner produced during the service life of a single image bearing member, and then is removed along with the drum cartridge as the drum cartridge is exchanged.
In the case of a brush roller for cleaning an image bearing member, it is placed in contact with an image bearing member. Therefore, the mechanism for transmitting a driving force to the brush roller, and the image bearing member, are worn by the brush roller. In other words, the usage of a brush roller is liable to reduce the service lives of the brush roller driving force transmission mechanism and the image bearing member. In order to solve this problem, the revolution of the brush roller, which comes in contact with the image bearing member, is desired to be as small as possible.
However, if a brush roller is rotated at a low revolution, toner particles become packed among the bristles of the brush, frequently varying the load which acts upon the brush roller driving force transmission mechanism. It is liable that this load fluctuation is transmitted to an image bearing member and reduces the quality of an image which is being formed.
Japanese Patent Laid-Open Application No. 176669/1983 discloses an image forming apparatus which comprises a cleaning apparatus for cleaning an electrostatic latent image bearing member. This cleaning apparatus, which is prior to the present invention, comprises a brushing member to which a positive bias is applied. In the case of this cleaning apparatus, the linear velocity Vp of the peripheral surface of the electrostatic latent image bearing member is 100 mm/sec, and the linear velocity Vb of the brushing member is 50 mm/sec. The linear velocity V
F
of the voltage applying means is 0 mm/sec.
However, the object of this invention disclosed in Japanese Patent Laid-Open Application No. 176669/1983 was to prevent the overall diameter of the brush from reducing. Thus, even if a brush roller were structured as disclosed in Patent Japanese Laid-Open Application No. 176669/1983, it would be impossible to prevent the fluctuation of the load generated by the brushing member from being transmitted to the electrostatic latent image bearing member.
SUMMARY OF THE INVENTION
The primary object of the present invention is to extend the service lives of an image bearing member and a brushing roller, and also to prevent the fluctuation of the load generated by a brushing roller from being transmitting to an image bearing member, so that it becomes possible to provide an image forming apparatus, a cleaning apparatus, and a process cartridge, which are capable of forming, or contributing to the formation of, images with a desirable quality for a long period of time.
Another object of the present invention is to provide an image forming apparatus, a cleaning apparatus, and a process cartridge, the number of the components of which is substantially smaller than those of the conventional ones.
Another object of the present invention is to provide a cleaning apparatus which comprises a brushing roller placed in contact with an image bearing member to remove the toner remaining on an image bearing member, and a second driving force transmission linkage, different from a first driving force transmission linkage for transmitting the driving force for driving the image bearing member, and in which the brushing roller is rotatively driven by the rotative force transmitted through the second driving force linkage, and the revolution at which the brushing roller is driven is lower than the revolution at which the image bearing member is driven, and also to provide a process cartridge and an image bearing member, which comprises such a cleaning apparatus.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 4297021 (1981-10-01), Tani et al.
patent: 4327992 (1982-05-01), Babicz
patent: 4451139 (1984-05-01), Yanagawa et al.
patent: 4475807 (1984-10-01), Toyoda et al.
patent: 4640608 (1987-02-01), Higaya et al.
patent: 4664505 (1987-05-01), Itaya et al.
patent: 4791455 (1988-12-01), Yamamoto et al.
patent: 4835807 (1989-06-01), Swift
patent: 5111251 (1992-05-01), Uno et al.
patent: 5235383 (1993-08-01), Tada et al.
patent: 5249026 (1993-09-01), Kojima
patent: 5471284 (1995-11-01), Fujii et al.
patent: 5497220 (1996-03-01), Inomata et al.
patent: 5521693 (1996-05-01), Kojima et al.
patent: 5587781 (1996-12-01), Auty et al.
patent: 5617195 (1997-04-01), Torimaru et al.
patent: 5625443 (1997-04-01), Ohta et al.
patent: 5740503 (1998-04-01), Nakamura
patent: 5940657 (1999-08-01), Yokomori et al.
patent: 5950049 (1999-09-01), Yokomori et al.
patent: 5963759 (1999-10-01), Kojima et al.
patent: 0 645 682 A2 (1995-03-01), None
patent: 57-111577 (1982-07-01), None
patent: 58-66981 (1983-04-01), None
patent: 58-62680 (1983-04-01), None
patent: 58-176669 (1983-10-01), None
patent: 59-113473 (1984-06-01), None
patent: 60-95473 (1985-05-01), None
patent: 60-168183 (1985-08-01), None
patent: 9-204133 (1997-08-01), None
Patent Abstracts
Kojima Hisayoshi
Mori Tomonori
Murayama Kazunari
Brase Sandra
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
LandOfFree
Cleaning apparatus equipped with brush roller, process... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cleaning apparatus equipped with brush roller, process..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cleaning apparatus equipped with brush roller, process... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2571312