EP0179253A1
Expired / Lapsed
EP
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Image forming apparatus
Assignee: Toshiba Corp
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Filing: 1985-09-12
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Granted: —
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Expires: 2005-09-12
Abstract
Abstract @ An image forming apparatus is provided with a light emitting element (92) for indicating a specific range of an original disposed on an original table (2), and the other light emitting elements (101) for erasing the electric charge on the surface of a photosensitive body (10) in response to the specific range of the original indicated by the light emitting element (92). A spot light is applied to the original on the original table by the light emitting element, and moved to specify the perimeter of an erasure range. In image forming, the specific range inside the perimeter is defined by an erasure range designating key (30f) and is developed through the black toner by a developing device (12,). On the other side, the specific range outside the perimeter is defined by the other erasure range designating key (30g) and is developed through the red toner by the other developing device (12,).
Inventors
- 👤 Junji C/O Patent Division Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 22:24
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/60; G03G15/605; G03G15/01; G03G15/36
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
255 words
An image forming apparatus comprising: a photosensitive body (10) holding an electric charge on the surface thereof; charging means (11) for uniformly applying electric charge to the surface of the photosensitive body (10); an original table (2) adapted to carry an original thereon; image exposure means (3) for exposing the surface of the photosensitive body (10) uniformly charged by the charging means (11) to a light representing an image of the original on the original table (2), thereby forming an electric charge pattern responsive to the original image on the surface of the photosensitive body (10); and developing means (12 1 , 12 2 ) for developing a latent image formed on the surface of the photosensitive body (10), which latent image is defined by the electric charge pattern, characterized by further comprising indicating means (91) for indicating a specific range of the original on the original table (2); and erasing means (100) for erasing the electric charge on the portion of the surface of the photosensitive body (10) other than that surface portion which corresponds to the specific range of the original indicated by the indicating means (91); and characterized in that said developing means (12 1 , 12 2 ) is adapted to alternatively supply developing agents of different types to the surface of the photosensitive body (10) and to develop by means of the supplied developing agent that portion of the surface of the photosensitive body (10) which corresponds to the specific range of the original indicated by the indicating means (91).
Claim 2
Dependent Claim
255 words
An image forming apparatus comprising: a photosensitive body (10) holding an electric charge on the surface thereof; charging means (11) for uniformly applying electric charge to the surface of the photosensitive body (10); an original table (2) adapted to carry an original thereon; image exposure means (3) for exposing the surface of the photosensitive body (10) uniformly charged by the charging means (11) to a light representing an image of the original on the original table (2), thereby forming an electric charge pattern responsive to the original image on the surface of the photosensitive body (10); and developing means (12 1 , 12 2 ) for developing a latent image formed on the surface of the photosensitive body (10), which latent image is defined by the electric charge pattern, characterized by further comprising indicating means (91) for indicating a specific range of the original on the original table (2); and erasing means (100) for erasing the electric charge on the portion of the surface of the photosensitive body (10) other than that surface portion which corresponds to the specific range of the original indicated by the indicating means (91); and characterized in that said developing means (12 1 , 12 2 ) is adapted to alternatively supply developing agents of different types to the surface of the photosensitive body (10) and to develop by means of the supplied developing agent that portion of the surface of the photosensitive body (10) which corresponds to the specific range of the original indicated by the indicating means (91).
Claim 3
Dependent Claim
51 words
The image forming apparatus according to claim 1, characterized in that said indicating means includes light emitting means (91) for applying a spot light to the original on the original table (2) from under the same, so that the perimeter of the specific range is defined by moving the spot light.
Claim 4
Dependent Claim
41 words
The image forming apparatus according to claim 2, characterized in that said indicating means (91) includes first setting means (30f) for setting the specific range inside the perimeter and second setting means (39g) for setting the specific range outside the perimeter.
Claim 5
Dependent Claim
58 words
The image forming apparatus according to claim 1, characterized in that said developing means includes a first developing unit (12 1 ) for supplying a first developing agent to the surface of the photosensitive body (10) and a second developing unit (12 2 ) for supplying a second developing agent to the surface of the photosensitive body (10).
Claim 6
Dependent Claim
39 words
The image forming apparatus according to claim 4, characterized in that said first developing agent includes a toner of a first color, and said second developing agent includes a toner of a second color different from the first color.
Claim 7
Dependent Claim
21 words
The image forming apparatus according to claim 5, characterized in that said first and second colors are black and red, respectively.
Claim 8
Dependent Claim
95 words
The image forming apparatus according to claim 3, characterized in that said developing means (12 1 , 12 2 ) alternatively supplies the first and second developing agents, so that that portion of the surface of the photosensitive body (10) which corresponds to the specific range set by the first setting means (30f) is developed by means of the first developing agent, and that portion of the surface of the photosensitive body (10) which corresponds to the specific range set by the second setting means (30g) is developed by means of the second developing agent.
Claim 9
Dependent Claim
39 words
The image forming apparatus according to claim 7, characterized in that said first developing agent includes a toner of a first color, and said second developing agent includes a toner of a second color different from the first color.
Claim 10
Dependent Claim
21 words
The image forming apparatus according to claim 8, characterized in that said first and second colors are black and red, respectively.
References Cited (Backward Citations)
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