Electrophotography – Image formation – Development
Reexamination Certificate
1999-12-15
2001-02-27
Chen, Sophia S. (Department: 2852)
Electrophotography
Image formation
Development
C399S088000
Reexamination Certificate
active
06195519
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a copier, printer, facsimile apparatus or similar image forming apparatus and more particularly to an image forming apparatus including a revolver type developing unit.
An electrophotographic process using powdery toner for developing an image and an apparatus for practicing the same are conventional. For example, a monocolor or a full-color image forming apparatus of the type using two-ingredient type developers usually includes sensors each for sensing the toner content of a particular developer, i.e., so-called T sensors. This type of apparatus executes process control in accordance with the outputs of the T sensors in order to enhance image quality.
It is a common practice with, e.g., a color image forming apparatus to use a rotary developing unit (revolver hereinafter) having a plurality of developing sections arranged therein. The problem with this kind of apparatus is that leads, for example, cannot be connected to the revolver. It follows that even if sensors and other electrical loads are arranged in the revolver, signals output form the loads cannot be sent to the body of the apparatus. The apparatus therefore fails the execute sufficient process control.
In light of the above, Japanese Patent Laid-Open Publication No. 8-69144, for example, discloses an image forming apparatus using photoelectric transducers for feeding power to a revolver and receiving information from the revolver. Also, Japanese Patent Laid-Open Publication No. 10-133446 teaches the use of a current transformer for feeding power and the use of optical communication for interchanging signals.
However, the photoelectric transducer scheme cannot maintain an electromotive force derived from the emission of light stable due to the rotation of the revolver, resulting in unstable generation of power in the revolver. Further, the quantity of light available with a light source and therefore the electromotive force sequentially decreases due to the limited life of the light source. In addition, the light source emitting light within the apparatus body effects a photoconductive element or image carrier. Even the current transformer and optical communication scheme renders the power feed and signal interchange unstable due to the rotation of the revolver and is apt to obstruct the transfer of necessary signals.
Technologies relating to the present invention are also disclosed in, e.g., Japanese Patent Laid-Open Publication Nos. 6-267627, 8-88600, and 11-174797.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an image forming apparatus realizing sure signal transfer and stable power feed between a revolver and an apparatus body.
In accordance with the present invention, an image forming apparatus including a revolver type developing unit rotatable with a plurality of developing sections arranged therein, and controlling electrical loads arranged in the developing unit without contacting the developing unit includes an apparatus body and power transfer sections respectively included in the developing unit and apparatus body for feeding power from the apparatus body to the developing unit without contacting each other. The power transfer sections are arranged such that when the developing unit is brought to a stop at a preselected developing position, the power transfer sections face each other.
Also, in accordance with the present invention, an image forming apparatus of the type described includes an apparatus body and connection units respectively included in the apparatus body and developing unit and each including a power feed section and a signal transmission/receipt section. The connection units face each other at parallel surfaces thereof.
REFERENCES:
patent: 4446461 (1984-05-01), Selleck
patent: 4697915 (1987-10-01), Hayashi et al.
patent: 5671470 (1997-09-01), Maruta et al.
patent: 5826146 (1998-10-01), Maruta et al.
patent: 5926670 (1999-07-01), Furuta et al.
patent: 5970278 (1999-10-01), Munakata
patent: 5983060 (1999-11-01), Namekata et al.
patent: 6006062 (1999-12-01), Takahashi et al.
patent: 6009293 (1999-12-01), Takami
patent: 6-267627 (1994-09-01), None
patent: 8-69144 (1996-03-01), None
patent: 8-88600 (1996-04-01), None
patent: 10-133446 (1998-05-01), None
patent: 11-174797 (1999-07-01), None
Isobe Takundo
Kato Shinji
Chen Sophia S.
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
Ricoh & Company, Ltd.
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