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US4990956A Expired / Lapsed US ⏱️ 0.0 years remaining

Image forming apparatus

Assignee: Toshiba Corp
•
Filing: 1989-04-05
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Granted: 1991-02-05
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Expires: 2009-04-05
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Abstract

Abstract An image forming apparatus comprises a main charger for charging the surface of a photosensitive drum, an exposure unit for illuminating an original and guiding light from the original onto the drum, thereby forming thereon an electrostatic latent image corresponding to an image of the original, a detector for detecting the size of the original, and an erase array for erasing an undesired electric charge on the photosensitive drum in accordance with the original size detected by the detector.

Inventors

  • 👤 Yasuhiro Iwata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 16:04
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/50; G03G15/04; G03G15/045; G03G15/047; G03G2215/00; G03G2215/04; G03G2215/0426; G03G2215/0429; G03G2215/0431; G03G2215/0434; G03G2215/0436; G03G2215/0439; G03G2215/0443; G03G2215/0446; G03G2215/0448; G03G2215/0451

Claims Analysis

Total Claims: 31
Claim 1
Independent Claim 107 words
An image forming apparatus comprising: means for carrying an original thereon; cover means movable between a first position in which cover means covers the original and the carrying means and a second position in which the cover means leaves exposed the original and the surrounding portion of the carrying means; image forming means for forming on an image carrier a first copy image corresponding to an image of the original on the carrying means and a second copy image corresponding to an image surrounding the original; and means for preventing the formation of the second copy image when the cover means is positioned in the second position.
Claim 2
Dependent Claim 107 words
An image forming apparatus comprising: means for carrying an original thereon; cover means movable between a first position in which cover means covers the original and the carrying means and a second position in which the cover means leaves exposed the original and the surrounding portion of the carrying means; image forming means for forming on an image carrier a first copy image corresponding to an image of the original on the carrying means and a second copy image corresponding to an image surrounding the original; and means for preventing the formation of the second copy image when the cover means is positioned in the second position.
Claim 3
Dependent Claim 33 words
The image forming apparatus according to claim 1, which further includes means for detecting the position of the cover means and controlling the preventing means according to the position of the cover means.
Claim 4
Dependent Claim 96 words
The image forming apparatus according to claim 2, which includes means for providing a support medium on the image carrier, and means for transferring the copy image from the image carrier to the support medium; and in which said preventing means includes means for comparing the size of the support medium to that of the first copy image formed on the image carrier, and a preventing device for preventing the second copy image from being formed on the image carrier when the size of the first copy image is smaller than that of the support image.
Claim 5
Dependent Claim 57 words
The image forming apparatus according to claim 1, wherein said image forming means includes a charging means for charging the image carrier, an optical means for forming an information light which carries original image information and surrounding image information, and applying the information image to the previously charged image carrier, thereby forming an electrostatic latent image thereon.
Claim 6
Dependent Claim 45 words
The image forming apparatus according to claim 4, wherein said optical means includes scanning means for optically scanning the original and the surrounding region, and guiding a reflected light from the original and the surrounding region onto the image carrier, thereby focusing the light thereon.
Claim 7
Dependent Claim 17 words
The image forming apparatus according to claim 1, wherein said size detecting means detects regular original sizes.
Claim 8
Dependent Claim 26 words
The image forming apparatus according to claim 6, wherein said size detecting means discriminates the regular original sizes by detecting an end portion of the original.
Claim 9
Dependent Claim 41 words
The image forming apparatus according to claim 7, wherein said size detecting means includes light emitting means for emitting light toward the original and the surrounding region and light receiving means for receiving light from the original and the surrounding region.
Claim 10
Dependent Claim 55 words
The image forming apparatus according to claim 5, wherein said size detecting means includes light emitting means for emitting light toward the original and the surrounding region, light receiving means for receiving light from the original and the surrounding region, and means for simultaneously moving the light emitting and receiving means and the scanning means.
Claim 11
Dependent Claim 24 words
The image forming apparatus according to claim 9, wherein said detecting means includes a plurality of sets of said light emitting and receiving means.
Claim 12
Dependent Claim 36 words
The image forming apparatus according to claim 1, wherein said image forming means includes latent image forming means for forming first and second latent images as the first and second copy images on the image carrier.
Claim 13
Dependent Claim 35 words
The image forming apparatus according to claim 7, further comprising visualizing means for visualizing the first and second latent image and transfer means for transferring the visualized images to the surface of a support medium.
Claim 14
Dependent Claim 72 words
The image forming apparatus according to claim 10, wherein said preventing means includes comparator means for comparing the size of the support medium to that of the image formed on the basis of the original detected by the detecting means, and a preventing device for preventing the second copy image from being formed on the image carrier when it is concluded that the image size is smaller than the support medium size.
Claim 15
Dependent Claim 45 words
The image forming apparatus according to claim 11, wherein said preventing device includes erase means for selectively erasing an electric charge within a predetermined range on the image carrier, and erase range setting means for setting a range to be erased by the erase means.
Claim 16
Dependent Claim 36 words
The image forming apparatus according to claim 12, wherein said erase means includes means for erasing the electric charge on the image carrier before the second latent image is formed by the latent image forming means.
Claim 17
Dependent Claim 20 words
The image forming apparatus according to claim 12, wherein said erase means includes means for erasing the second latent image.
Claim 18
Dependent Claim 35 words
The image forming apparatus according to claim 11, wherein said preventing device prevents the formation of the peripheral edge portion of the first copy image, as well as the formation of the second copy image.
Claim 19
Dependent Claim 48 words
The image forming apparatus according to claim 10, further comprising carrying means for carrying the original to be scanned by the scanning means, cover means for covering the original on the carrying means, and cover detecting means for detecting the presence of the cover means on the original.
Claim 20
Dependent Claim 93 words
The image forming apparatus according to claim 16, wherein said preventing means includes comparator means for comparing the size of the support medium to that of the image formed on the basis of the size of the original detected by the detecting means, and a preventing device for preventing the second copy image from being formed on the image carrier when it is concluded that the image size is smaller than the support medium size and if the presence of the cover means on the original is detected by the cover detecting means.
Claim 21
Dependent Claim 86 words
An image forming apparatus comprising: an image carrier; charging means for charging the image carrier; illumination means for illuminating an original; optical means for guiding light reflected from the original onto the charged image carrier, thereby forming an electrostatic latent image thereon; detecting means for detecting an image region corresponding to an image of the original by detecting the light guided by the optical means; and erase means for erasing an electric charge on the image carrier corresponding to a no-image region outside the image region.
Claim 22
Dependent Claim 86 words
An image forming apparatus comprising: an image carrier; charging means for charging the image carrier; illumination means for illuminating an original; optical means for guiding light reflected from the original onto the charged image carrier, thereby forming an electrostatic latent image thereon; detecting means for detecting an image region corresponding to an image of the original by detecting the light guided by the optical means; and erase means for erasing an electric charge on the image carrier corresponding to a no-image region outside the image region.
Claim 23
Dependent Claim 26 words
The image forming apparatus according to claim 20, wherein said optical means includes focusing means for focusing the light from the original on the image carrier.
Claim 24
Dependent Claim 28 words
The image forming apparatus according to claim 20, wherein said detecting means detects those beams of the light from the original which are transmitted through the focusing means.
Claim 25
Dependent Claim 29 words
The image forming apparatus according to claim 20, wherein said detecting means detects those beams of the light from the original which are not transmitted through the focusing means.
Claim 26
Dependent Claim 45 words
The image forming apparatus according to claim 20, wherein said detecting means includes a detector adapted to receive the light from the original and deliver image information corresponding to the received light, and focusing means for focusing the light from the original on the detector.
Claim 27
Dependent Claim 136 words
An image forming apparatus comprising: image forming means for forming on an image carrier a first copy image corresponding to an image of the original on the carrying means and a second copy image corresponding to an image of a region surrounding the original; means for detecting the size of the original; means for preventing the formation of the second copy image in accordance with the result of detection by the size detecting means; and means for moving the image forming means and size detecting means simultaneously against the original in the same direction two times in every copying cycle so that the size detecting means detects the size of the original while moving for the first time, and the image forming means forms the copy image on the carrier while moving for the second time.
Claim 28
Dependent Claim 136 words
An image forming apparatus comprising: image forming means for forming on an image carrier a first copy image corresponding to an image of the original on the carrying means and a second copy image corresponding to an image of a region surrounding the original; means for detecting the size of the original; means for preventing the formation of the second copy image in accordance with the result of detection by the size detecting means; and means for moving the image forming means and size detecting means simultaneously against the original in the same direction two times in every copying cycle so that the size detecting means detects the size of the original while moving for the first time, and the image forming means forms the copy image on the carrier while moving for the second time.
Claim 29
Dependent Claim 109 words
An image forming apparatus comprising: an image carrier movable in one direction; image forming means for scanning the original in one direction to form a first copy image corresponding to an image of the original and a second copy image corresponding to an image of a region surrounding the original onto the image carrier during the movement of the image carrier; means for detecting the size of the original; and means for preventing the formation of the second copy image in accordance with the result of detection by the size detecting means, while the image forming means scans the original and the image carrier is moved in said direction.
Claim 30
Dependent Claim 109 words
An image forming apparatus comprising: an image carrier movable in one direction; image forming means for scanning the original in one direction to form a first copy image corresponding to an image of the original and a second copy image corresponding to an image of a region surrounding the original onto the image carrier during the movement of the image carrier; means for detecting the size of the original; and means for preventing the formation of the second copy image in accordance with the result of detection by the size detecting means, while the image forming means scans the original and the image carrier is moved in said direction.
Claim 31
Dependent Claim 60 words
The image forming apparatus according to claim 26, wherein said preventing means includes erase means having a plurality of erase elements linearly arranged at right angles to the moving direction of the image carrier, and means for selectively driving the erase elements during the movement of the image carrier so that the formation of the second copy image is prevented.

References Cited (Backward Citations)

US4692019A Cited
US4713550A Cited
US4745438A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-02-04 1994-08-06 1995-02-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-02-04 1998-08-06 1999-02-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-02-04 2002-08-06 2003-02-05 $7700.00 Window Closed / Lapsed

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