Electrophotography – Having particular structure – Modular or displaceable
Reexamination Certificate
1998-06-23
2001-05-22
Braun, Fred L (Department: 2852)
Electrophotography
Having particular structure
Modular or displaceable
Reexamination Certificate
active
06236821
ABSTRACT:
FIELD OF THE INVENTION AND RELATED ART
The present invention relates to a connecting pin that is used in a process cartridge removably installable in an electrophotographic image forming apparatus, and the process cartridge. In this specification, electrophotographic image forming apparatus refers to an apparatus which forms an image on recording medium with the use of an electrophotographic image forming system. It includes an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED printer, or the like), a facsimile machine, a word processor, and the like.
The term a “process cartridge” refers to a cartridge that is rendered removably installable in the main assembly of an electrophotographic image forming apparatus, and integrally comprises an electrophotographic photosensitive member, and at least one of three means: a charging means for charging an electrophotographic photosensitive member; a developing means for developing a latent image formed on the peripheral surface of the electrophotographic photosensitive member; and a cleaning means for removing the developer remaining on the peripheral surface of the electrophotographic photosensitive member.
In some of the image forming apparatuses which employ an electrophotographic photosensitive image forming system, a process cartridge system is employed. In the case of this type of process cartridge system, an electrophotographic photosensitive member, and one or more processing means, which work with the electrophotographic photosensitive member, are integrally placed in a cartridge. With the employment of this type of process cartridge system, the image forming apparatus can be maintained by a user himself, without the need for relying on service personnel, and therefore, the usability of the apparatus is greatly improved.
A typical structure of such a process cartridge comprises two frames, for example, a cleaning unit frame and an image developing unit frame, which are connected to each other. The cleaning unit frame contains an electrophotographic photosensitive drum, a charging device, and a cleaning device, and the image developing unit frame comprises an image developing means frame and a toner frame. The developing means frame supports a developing means, and the toner frame constitutes a toner chamber. The cleaning unit frame, and the image developing unit frame are connected in such a manner that the two frames are rendered pivotable about a connecting pin (axis). Further, the two frames are kept under such force that is generated with the use of an elastic member, for example, a spring, and that maintains a predetermined positional relationship between the photosensitive drum and the developing means. This two piece structure has various functional advantages and merits. For example, the two piece structure makes it easier to keep the pressure applied upon the photosensitive drum by an image developing roller, at a proper level, and it is also easier to maintain the proper gap between the peripheral surfaces of the photosensitive drum and the image developing roller. Further, the two piece structure makes it easier to mold the structural components of the process cartridge, and also to assemble the components into the process cartridge.
SUMMARY OF THE INVENTION
Accordingly, the primary object of the present invention is to provide a connecting pin which assures that the two frames of a process cartridge are properly connected.
Another object of the present invention is to provide a connecting pin which does not easily disengage from the frames of a process cartridge.
Another object of the present invention is to provide a coupling pin for coupling a first frame and a second frame of a process cartridge detachably mountable relative to a main assembly of an electrophotographic image forming apparatus, comprising: (a) a first shaft portion for being press-fitted into a first hole formed in the first frame; (b) a second shaft portion for being press-fitted into a second hole formed in the first frame, wherein the second shaft portion is upstream of the first shaft portion in a direction of press-fitting of the coupling pin, and the second shaft portion has an outer diameter which is larger than that of the first shaft portion; and (c) a third shaft portion for being loosely fitted into a hole formed in the second frame with a gap between the third shaft portion and inside surface of the hole of the second shaft.
Another object of the present invention is to provide a process cartridge that comprises two frames connected with the connecting pin described above.
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: 5294960 (1994-03-01), Nomura et al.
patent: 5623328 (1997-04-01), Tsuda et al.
patent: 5640229 (1997-06-01), Nakahara
patent: 5659847 (1997-08-01), Tsuda et al.
patent: 5749027 (1998-05-01), Ikemoto et al.
patent: 5752131 (1998-05-01), Fujiwara et al.
patent: 5768669 (1998-06-01), Yokoyama
patent: 5774766 (1998-06-01), Karakama et al.
patent: 5828928 (1998-10-01), Sasago et al.
patent: 5937242 (1999-08-01), Yokoyama et al.
Numagami Atsushi
Watanabe Kazushi
Yokoyama Katsunori
Braun Fred L
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
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