US4140386A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic apparatus
Assignee: Ricoh Co Ltd
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Filing: 1977-09-13
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Granted: 1979-02-20
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Expires: 1997-09-13
Abstract
Abstract For producing a plurality of copies of an original document which has a length less than one-half a maximum document length which can be accomodated by the apparatus, a plurality of electrostatic images are formed on a rotating photoconductive drum by alternately forming an image on one image space and letting one or more image spaces pass before forming the next image. Development and transfer of the electrostatic images are effected during a last imaging revolution of the drum and may be further effected during subsequent revolutions of the drum for repeated development and transfer using the same electrostatic images. The number of electrostatic images formed on the drum is computed as a function of the length of the original document and the number of copies to be made to minimize the number of revolutions of the drum required to produce the copies and thereby maximize the copying speed. The number of electrostatic images formed is not necessarily the maximum number which can be formed on the drum.
Inventors
- 👤 Toyokazu Satomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:15
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/28; G03G15/30; G03G15/307
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
132 words
An electrophotographic apparatus comprising: a photoconductive member having a continuously rotatably moving endless surface; imaging means operatively arranged relative to the photoconductive member for forming a plurality of identical, circumferentially spaced electrostatic images on the photoconductive member; developing and transfer means for developing the electrostatic images to form toner images and transferring the toner images to copy sheets; and control means for controlling the imaging means and the developing and transfer means, the control means being operative to compute as a function of a number of copies to be made and a circumferential length of each of the electrostatic images, a number of the electrostatic images to be formed on the photoconductive member for producing the number of copies to be made in a minimum number of revolutions of the photoconductive member.
Claim 2
Dependent Claim
132 words
An electrophotographic apparatus comprising: a photoconductive member having a continuously rotatably moving endless surface; imaging means operatively arranged relative to the photoconductive member for forming a plurality of identical, circumferentially spaced electrostatic images on the photoconductive member; developing and transfer means for developing the electrostatic images to form toner images and transferring the toner images to copy sheets; and control means for controlling the imaging means and the developing and transfer means, the control means being operative to compute as a function of a number of copies to be made and a circumferential length of each of the electrostatic images, a number of the electrostatic images to be formed on the photoconductive member for producing the number of copies to be made in a minimum number of revolutions of the photoconductive member.
Claim 3
Dependent Claim
53 words
An apparatus as in claim 1, in which the control means controls the imaging means to form the electrostatic images on a plurality of equally circumferentially spaced identical image spaces on the photoconductive member, a maximum number of the electrostatic images to be formed being equal to a number of the image spaces.
Claim 4
Dependent Claim
53 words
An apparatus as in claim 2, in which the control means controls the imaging means to form the electrostatic images on the photoconductive member by alternately energizing the imaging means as one of the image spaces passes thereby and de-energizing the imaging means as at least one of the image spaces passes thereby.
Claim 5
Dependent Claim
54 words
An apparatus as in claim 3, in which the control means is operative to control the imaging means to form the electrostatic images on the photoconductive member during a plurality of revolutions of the photoconductive member, the control means energizing the developing and transfer means during a last revolution of said plurality of revolutions.
Claim 6
Dependent Claim
50 words
An apparatus as in claim 3, in which the imaging means comprises a scan member movable in a scan direction and a return direction, the scan member being moved in the scan direction when the imaging means is energized and in the return direction when the imaging means is de-energized.
Claim 7
Dependent Claim
22 words
An apparatus as in claim 5, in which the scan member moves in the scan and return directions as a same speed.
Claim 8
Dependent Claim
36 words
An apparatus as in claim 3, in which the imaging means comprises a shutter means controlled by the control means to open when the imaging means is energized and closed when the imaging means is de-energized.
Claim 9
Dependent Claim
101 words
An apparatus as in claim 3, in which the imaging means comprises: a document holder; a first mirror movable at a velocity V in the scan direction relative to the document holder to reflect a light image from the document holder; a second mirror movable at a velocity V/2 in the scan direction to reflect the light image from the first mirror; a fixed converging lens having a reflecting rear plane surface to reflect the light image from the second mirror; and a third mirror to reflect the light image from the converging lens onto the surface of the photoconductive member.
References Cited (Backward Citations)
US3736055A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-19 | 1982-08-21 | 1983-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-19 | 1986-08-21 | 1987-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-19 | 1990-08-21 | 1991-02-20 | $7700.00 | Window Closed / Lapsed |