US4970552A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Toner contamination preventive means
Assignee: Ricoh Co Ltd
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Filing: 1988-05-20
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Granted: 1990-11-13
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Expires: 2008-05-20
Abstract
Abstract An electrostatic photographic image forming apparatus for forming an electrostatic image on a photosensitive member by the light beam from a writing system and transferring to a transfer paper the image which has been made visible by a development apparatus. A shutter or a toner contamination preventive means is provided at the space defining an optical path extending between the photosensitive member and the lens of the writing system nearest to the photosensitive member.
Inventors
- 👤 Keiji Okamoto
- 👤 Hiromi Takada
- 👤 Hideo Aoki
- 👤 Toshio Shimazaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:48
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/04; G03G15/043; G03G15/0435
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
106 words
An image forming apparatus comprising: a photosensitive member; a writing system for forming an electrostatic latent image on said photosensitive member by a light beam; a development apparatus for developing said latent image; a transfer charger for transferring a visual image on said photosensitive member to a transfer paper; and a toner contamination preventive means for preventing the contamination of a lens disposed in an optical path of the writing system, wherein said toner contamination preventive means includes an adhesive member attached to at least a part of a wall defining said optical path, and said optical path extends from said photosensitive member to said lens.
Claim 2
Dependent Claim
106 words
An image forming apparatus comprising: a photosensitive member; a writing system for forming an electrostatic latent image on said photosensitive member by a light beam; a development apparatus for developing said latent image; a transfer charger for transferring a visual image on said photosensitive member to a transfer paper; and a toner contamination preventive means for preventing the contamination of a lens disposed in an optical path of the writing system, wherein said toner contamination preventive means includes an adhesive member attached to at least a part of a wall defining said optical path, and said optical path extends from said photosensitive member to said lens.
Claim 3
Dependent Claim
145 words
An image forming apparatus comprising: a photosensitive member; a writing system for forming an electrostatic latent image on said photosensitive member by a light beam; a development apparatus for developing said latent image; a transfer charger for transferring a visual image on said photosensitive member to a transfer paper; plates disposed beneath said photosensitive member forming an acute angle and extending from said photosensitive member to a lens disposed in said writing system for defining an optical path of said writing system, an upper portion and a lower portion of one of said plates providing an opening for said optical path; and a toner contamination preventative means for preventing contamination of said lens including a step-back defined by said upper portion and said lower portion of said one of said plates, said upper portion projecting over said lower portion to partially cover said lower portion.
Claim 4
Dependent Claim
145 words
An image forming apparatus comprising: a photosensitive member; a writing system for forming an electrostatic latent image on said photosensitive member by a light beam; a development apparatus for developing said latent image; a transfer charger for transferring a visual image on said photosensitive member to a transfer paper; plates disposed beneath said photosensitive member forming an acute angle and extending from said photosensitive member to a lens disposed in said writing system for defining an optical path of said writing system, an upper portion and a lower portion of one of said plates providing an opening for said optical path; and a toner contamination preventative means for preventing contamination of said lens including a step-back defined by said upper portion and said lower portion of said one of said plates, said upper portion projecting over said lower portion to partially cover said lower portion.
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JPS535631A
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JPS5627170A
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JPS56133747A
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US4469430A
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JPS5929276A
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JPS6021066A
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JPS6052875A
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JPS6275658A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-11-12 | 1994-05-14 | 1994-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-12 | 1998-05-14 | 1998-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-12 | 2002-05-14 | 2002-11-13 | $7700.00 | Window Closed / Lapsed |