Electrophotography – Image formation – Transfer
Patent
1998-03-19
1999-09-21
Brase, Sandra
Electrophotography
Image formation
Transfer
399223, 399302, G03G 1501
Patent
active
059565527
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a color image forming apparatus used in a color printer, a color copying machine or a color facsimile. More specifically, the present invention relates to acceleration and miniaturization of a color image forming apparatus that forms a color toner image by superimposing toner images of various colors using electrophotography.
BACKGROUND OF THE INVENTION
As a prior art example of such a color image forming apparatus, an outline of the structure of the color printer described in Publication of Unexamined Patent Application (Tokkai) No. Hei 7-36246 is explained. As can be seen in FIG. 8, which shows the internal structure viewed from the side, this apparatus comprises an intermediate transfer belt unit 201 including a transfer belt 202, a primary transfer roller 203, a secondary transfer roller 204, a cleaner roller 205, and a waste toner reservoir 206. Composition of color toner images is performed on the transfer belt 202.
Four image forming units 207Bk, 207Y, 207M and 207C for black, yellow, magenta and cyan, each unit being of sector shape in cross section, are arranged circularly in the middle of the printer to form a group of image forming units 208. When an image forming unit 207Bk, 207Y, 207M or 207C is set properly in the printer, mechanical and electrical connection systems are established between one of the image forming units 207Bk, 207Y, 207M and 207C and the machine body side via mutual coupling members, so that both sides are mechanically and electrically connected.
The image forming units 207Bk, 207Y, 207M and 207C are supported by a supporter, which can revolve around a cylindrical shaft 209, and are collectively rotated by a motor. Each image forming unit is successively moved by rotation to an image forming position 210, where it opposes the primary transfer roller 203 spanning the intermediate transfer belt 202. The image forming position 210 is also the exposure position for exposure by a laser beam 211.
Numeral 212 is a laser exposing device arranged in the lower part of the printer. The laser signal beam 211 passes through a light path opening 213 between the image forming units 207M and 207C, and through an opening provided in the cylindrical shaft 209, and enters a mirror 214, which is positioned inside the shaft 209 and fixed directly to the machine body. The laser beam 211 reflected by the mirror 214 enters the image forming unit 207Bk located at the image forming position 210 through an exposure opening 215, and passes through an exposure space between a developing device 216 and a cleaner 217, arranged on the upper and the lower side in the image forming unit, and enters an exposure portion on the left side of the photosensitive drum 218. The laser signal beam is scanned by the exposing device along the direction of the axis of the photosensitive drum 218 and a latent image is formed. The toner image is formed on the surface of the photosensitive drum 218 by development with the developing device 216.
The toner image formed on the photosensitive drum 218 is transferred to the intermediate transfer belt 202. Then, the group of image forming units 208 rotates by 90 degrees, so that the yellow image forming unit 207Y moves to the image forming position 210. An operation similar to the operation explained above for the formation of the black image is performed to form a yellow toner image overlaying the black toner image that has already been formed on the intermediate transfer belt 202. Similar operations as explained above are performed using the magenta and cyan image forming units to compose a fall color image on the intermediate transfer belt 202. This full color image is further transferred onto a recording paper by a secondary transfer roller 219, and after the image on the paper is fixed by a fixing device 220, the paper is ejected.
When the image formation of one sheet is finished, the group of image forming units 208 rotates another 90 degrees, so that the black image forming unit 207Bk returns to the image forming
REFERENCES:
patent: 4662739 (1987-05-01), Sakai et al.
patent: 4743938 (1988-05-01), Ohno
patent: 5255063 (1993-10-01), Ideyama et al.
patent: 5325151 (1994-06-01), Kimura et al.
patent: 5442428 (1995-08-01), Takahashi et al.
patent: 5515140 (1996-05-01), Atsumi et al.
patent: 5528343 (1996-06-01), Tada et al.
patent: 5565975 (1996-10-01), Kumon et al.
patent: 5585911 (1996-12-01), Hattori et al.
patent: 5587769 (1996-12-01), Sawada et al.
patent: 5587783 (1996-12-01), Nakamura et al.
patent: 5610701 (1997-03-01), Terada et al.
patent: 5612771 (1997-03-01), Yamamoto et al.
patent: 5666596 (1997-09-01), Yoo
patent: 5669046 (1997-09-01), Yoshida et al.
patent: 5787326 (1998-07-01), Ogawa et al.
patent: 5809380 (1998-09-01), Katakabe et al.
Asakura Kenji
Katakabe Noboru
Terada Hiroshi
Yamamoto Hajime
Yoshikawa Masanori
Brase Sandra
Chen Sophia S.
Matsushita Electric - Industrial Co., Ltd.
LandOfFree
Color image forming apparatus comprising a regular mode and a hi does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Color image forming apparatus comprising a regular mode and a hi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color image forming apparatus comprising a regular mode and a hi will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-90590