US4792828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image forming apparatus for forming a plurality of image from different originals on one transfer sheet
Assignee: Canon Inc
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Filing: 1986-07-29
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Granted: 1988-12-20
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Expires: 2006-07-29
Abstract
Abstract An image forming apparatus capable of effecting plural image forming operations on one transfer sheet includes an image transfer device for transferring an image on the transfer sheet, an image magnification changing mechanism for changing the magnification of the image to be transferred onto the transfer sheet, and a control device for controlling the magnification changing mechanism in accordance with deformation of the transfer sheet caused by an image forming operation on the transfer sheet, after a first image is formed on the transfer sheet and before a second image is formed on the same transfer sheet, whereby those images are correctly registered.
Inventors
- 👤 Takashi Ozawa
- 👤 Yasuyoshi Yamamoto
- 👤 Masashi Ohashi
- 👤 Akiyoshi Kimura
- 👤 Nobukazu Sasaki
- 👤 Toshirou Kasamura
- 👤 Atsushi Kubota
- 👤 Tatsuya Shiratori
- 👤 Toshihiko Kusumoto
- 👤 Michiro Koike
- 👤 Ken Tanabe
- 👤 Hidetoshi Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:57
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/50; G03G15/5029; G03G15/04; G03G15/041; G03G15/5095; G03G2215/00; G03G2215/00362; G03G2215/00535; G03G2215/00556; G03G2215/00578; G03G2215/00586; G03G2215/0059
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
72 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; and control means for controlling said magnification changing means in accordance with the deformation of the transfer sheet during an image forming operation on the transfer sheet.
Claim 2
Dependent Claim
72 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; and control means for controlling said magnification changing means in accordance with the deformation of the transfer sheet during an image forming operation on the transfer sheet.
Claim 3
Dependent Claim
23 words
An apparatus according to claim 1 wherein said magnification changing means changes the longitudinal magnification and the lateral magnification at the same rate.
Claim 4
Dependent Claim
45 words
An apparatus according to claim 1, wherein said magnification changing means includes longitudinal magnification changing means for changing the magnification in the longitudinal direction of the transfer sheet and lateral magnification changing means for changing the magnification in the lateral direction of the transfer sheet.
Claim 5
Dependent Claim
105 words
An apparatus according to claim 3, wherein said image forming apparatus includes: original supporting means for supporting an original; a photosensitive member for bearing a toner image to be transferred onto the transfer sheet; and an optical system, including a lens, for scanning the original and exposing said photosensitive member to an image of the original, and wherein said longitudinal magnification changing means changes the longitudinal magnification by changing the ratio of the scanning speed of the optical system and the moving speed of the photosensitive member, and wherein said lateral magnification changing means changes the lateral magnification by changing the position of the lens.
Claim 6
Dependent Claim
24 words
An apparatus according to claim 1, wherein said image forming apparatus is capable of forming superimposed images on one side of the transfer sheet.
Claim 7
Dependent Claim
84 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; deformation detecting means for detecting the amount of deformation of the transfer sheet resulting from an image forming operation; and control means for controlling said magnification changing means on the basis of information detected by said deformation detecting means.
Claim 8
Dependent Claim
84 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; deformation detecting means for detecting the amount of deformation of the transfer sheet resulting from an image forming operation; and control means for controlling said magnification changing means on the basis of information detected by said deformation detecting means.
Claim 9
Dependent Claim
63 words
An apparatus according to claim 6, wherein said image forming apparatus includes fixing means for fixing the image transferred to the transfer sheet, and wherein said deformation means includes means for detecting the size of the transfer sheet after deformation, the means for detecting the size after deformation being disposed downstream of said fixing means with respect to a transfer sheet conveying direction.
Claim 10
Dependent Claim
50 words
An apparatus according to claim 7, wherein said deformation detecting means includes means for detecting the size of the transfer sheet before deformation, the means for detecting the size of the transfer sheet before deformation being disposed upstream of said fixing means with respect to a transfer sheet conveying direction.
Claim 11
Dependent Claim
60 words
An apparatus according to claim 6, wherein said deformation detecting means includes means for detecting the size of the transfer sheet before deformation and means for detecting the size of the transfer sheet after deformation, and wherein the amount of deformation of the transfer sheet is determined by comparing the sizes of the transfer sheet before and after the deformation.
Claim 12
Dependent Claim
45 words
An apparatus according to claim 6, wherein said magnification changing means includes longitudinal magnification changing means for changing the magnification in the longitudinal direction of the transfer sheet and lateral magnification changing means for changing the magnification in the lateral direction of the transfer sheet.
Claim 13
Dependent Claim
105 words
An apparatus according to claim 10, wherein said image forming apparatus includes: original supporting means for supporting an original; a photosensitive member for bearing a toner image to be transferred onto the transfer sheet; and an optical system, including a lens, for scanning the original and exposing said photosensitive member to an image of the original, and wherein said longitudinal magnification changing means changes the longitudinal magnification by changing the ratio of the scanning speed of the optical system and the moving speed of a photosensitive member, and wherein said lateral magnification changing means changes the lateral magnification by changing the position of the lens.
Claim 14
Dependent Claim
90 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; and control means for controlling said magnification changing means to change the magnification at a predetermined rate to effect the image forming operation at the changed magnification for the second and subsequent, if any, formation of the image to be transferred onto the transfer sheet.
Claim 15
Dependent Claim
90 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; and control means for controlling said magnification changing means to change the magnification at a predetermined rate to effect the image forming operation at the changed magnification for the second and subsequent, if any, formation of the image to be transferred onto the transfer sheet.
Claim 16
Dependent Claim
45 words
An apparatus according to claim 12, wherein said magnification changing means includes longitudinal magnification changing means for changing the magnification in the longitudinal direction of the transfer sheet and lateral magnification changing means for changing the magnification in the lateral direction of the transfer sheet.
Claim 17
Dependent Claim
105 words
An apparatus according to claim 13, wherein said image forming apparatus includes: original supporting means for supporting an original; a photosensitive member for bearing a toner image to be transferred onto the transfer sheet; and an optical system, including a lens, for scanning the original and exposing said photosensitive member to an image of the original, and wherein said longitudinal magnification changing means changes the longitudinal magnification by changing the ratio of the scanning speed of the optical system and the moving speed of the photosensitive member, and wherein siad lateral magnification changing means changes the lateral magnification by changing the position of the lens.
Claim 18
Dependent Claim
35 words
An apparatus according to claim 12, wherein said control means causes said magnification changing means to change the magnification at the same rate in the longitudinal direction and the lateral direction of the transfer sheet.
Claim 19
Dependent Claim
38 words
An apparatus according to claim 12, wherein said control means causes said magnification changing means to change the magnification in a longitudinal direction of the transfer sheet and a magnification in the lateral direction thereof at different rates.
Claim 20
Dependent Claim
30 words
An apparatus according to claim 12, wherein said control means causes said magnification changing means to change the magnification at different rates depending on the size of the transfer sheet.
Claim 21
Dependent Claim
101 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; fixing means for fixing the image transferred to the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; and control means for controlling said magnification changing means to change the magnification at a predetermined rate for a second formation of the image to be transferred onto the transfer sheet, wherein the transfer sheet passes through the fixing means before the second image formation.
Claim 22
Dependent Claim
101 words
An image forming apparatus capable of effecting plural image forming operations on one transfer sheet, comprising: image transfer means for transferring an image on the transfer sheet; fixing means for fixing the image transferred to the transfer sheet; image magnification changing means for changing the magnification of the image to be transferred onto the transfer sheet; and control means for controlling said magnification changing means to change the magnification at a predetermined rate for a second formation of the image to be transferred onto the transfer sheet, wherein the transfer sheet passes through the fixing means before the second image formation.
Claim 23
Dependent Claim
45 words
An apparatus according to claim 18, wherein said magnification changing means includes longitudinal magnification changing means for changing the magnification in the longitudinal direction of the transfer sheet and lateral magnification changing means for changing the magnification in the lateral direction of the transfer sheet.
Claim 24
Dependent Claim
105 words
An apparatus according to claim 19, wherein said image forming apparatus includes: original supporting means for supporting an original; a photosensitive member for bearing a toner image to be transferred onto the transfer sheet; and an optical system, including a lens, for scanning the original and exposing said photosensitive member to an image of the original, and wherein said longitudinal magnification changing means changes the longitudinal magnification by changing the ratio of the scanning speed of the optical system and the moving speed of the photosensitive member, and wherein said lateral magnification changing means changes the lateral magnification by changing the position of the lens.
Claim 25
Dependent Claim
35 words
An apparatus according to claim 18, wherein said control means causes said magnification changing means to change the magnification at the same rate in the longitudinal direction and the lateral direction of the transfer sheet.
Claim 26
Dependent Claim
38 words
An apparatus according to claim 18, wherein said control means causes said magnification changing means to change the magnification in the longitudinal direction of the transfer sheet and the magnification in the lateral direction thereof at different rates.
Claim 27
Dependent Claim
30 words
An apparatus according to claim 18, wherein said control means causes said magnification changing means to change the magnification at different rates depending on the size of the transfer sheet.
Claim 28
Dependent Claim
21 words
An apparatus according to claim 7, wherein said fixing means includes heating means for fixing the image on the transfer sheets.
Claim 29
Dependent Claim
21 words
An apparatus according to claim 8, wherein said fixing means includes heating means for fixing the image on the transfer sheets.
Claim 30
Dependent Claim
21 words
An apparatus according to claim 18, wherein said fixing means includes heating means for fixing the image on the transfer sheets.
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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) | 1991-12-20 | 1992-06-20 | 1992-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-20 | 1996-06-20 | 1996-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-20 | 2000-06-20 | 2000-12-20 | $7700.00 | Window Closed / Lapsed |