Patent US5296903A successfully refreshed from Google Patents.
US5296903A
Expired / Lapsed
US
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Image forming apparatus having control based on detected toner charge and transfer efficiency
Assignee: Canon Inc
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Filing: 1992-10-15
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Granted: 1994-03-22
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Expires: 2012-10-15
Abstract
Abstract An image forming apparatus has an image bearing member; a toner image forming device for forming a toner image on the image bearing member; a transfer charger for transferring the toner image from the image bearing member onto a transfer material; a first detector for detecting toner charge amount before image transfer onto the transfer material; a second detector for detecting the efficiency of the image transfer; and a controller for controlling a condition of image transfer operation in accordance with outputs of the first and second detector.
Inventors
- 👤 Akio Suzuki
- 👤 Hisashi Fukushima
- 👤 Haruhiko Moriguchi
- 👤 Yasushi Miura
- 👤 Nobuatsu Sasanuma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:45
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/163; G03G15/1635; G03G15/1645; G03G15/01; G03G15/0105; G03G15/0131
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
87 words
An image forming apparatus, comprising: an image bearing member; toner image forming means for forming a toner image on said image bearing member; transfer charging means for transferring the toner image from said image bearing member onto a transfer material; first detecting means for detecting toner charge amount before image transfer onto the transfer material; second detecting means for detecting efficiency of the image transfer; and control means for controlling a condition of image transfer operation in accordance with outputs of said first and second detecting means.
Claim 2
Dependent Claim
87 words
An image forming apparatus, comprising: an image bearing member; toner image forming means for forming a toner image on said image bearing member; transfer charging means for transferring the toner image from said image bearing member onto a transfer material; first detecting means for detecting toner charge amount before image transfer onto the transfer material; second detecting means for detecting efficiency of the image transfer; and control means for controlling a condition of image transfer operation in accordance with outputs of said first and second detecting means.
Claim 3
Dependent Claim
38 words
An apparatus according to claim 1, wherein said control means controls at least one of the toner charge amount and an electric field for the image transfer in accordance with outputs of said first and second detecting means.
Claim 4
Dependent Claim
46 words
An apparatus according to claim 2, further comprising toner charging means for charging the toner image after formation of the toner image on said image bearing member and before the image transfer, and said control means controls the toner charge amount by the toner charging means.
Claim 5
Dependent Claim
25 words
An apparatus according to claim 1, wherein said first detecting means detects an electric current of said transfer charging means contributable to the image transfer.
Claim 6
Dependent Claim
40 words
An apparatus according to claim 1, further comprising a transfer material carrying member for carrying the transfer material, wherein the toner image on said image bearing member is transferred onto the transfer material carried on said transfer material carrying member.
Claim 7
Dependent Claim
40 words
An apparatus according to claim 4, further comprising a transfer material carrying member for carrying the transfer material, wherein the toner image on said image bearing member is transferred onto the transfer material carried on said transfer material carrying member.
Claim 8
Dependent Claim
46 words
An apparatus according to claim 6, wherein said transfer charging means is contactable to such a side of the transfer material carrying member as is remote from said image bearing member, and said first detecting means detects an electric current supplied to said transfer charging means.
Claim 9
Dependent Claim
26 words
An apparatus according to claim 7, wherein when said first detecting means detects the electric current, the transfer charging means is supplied with a constant voltage.
Claim 10
Dependent Claim
46 words
An apparatus according to claim 4, wherein said transfer charging means is in the form of a corona charging means having a wire electrode and a shield electrode, and wherein said first detecting means detects electric currents flowing to the wire electrode and the shield electrode.
Claim 11
Dependent Claim
51 words
An apparatus according to claim 1, wherein said second detecting means includes a first sensor for detecting a density of the toner image on said image bearing member before the image transfer and a second sensor for detecting density of residual toner on said image bearing member after the image transfer.
Claim 12
Dependent Claim
62 words
An apparatus according to claim 5, wherein the toner image can be transferred onto the transfer material carrying member, and wherein said second detecting means includes a first sensor for detecting a toner density on said image bearing member before the image transfer and a second sensor for detecting a toner density on the transfer material carrying member after the image transfer.
Claim 13
Dependent Claim
39 words
An apparatus, according to claim 5, wherein plural color toner images can be formed on said image bearing member, and the toner images are sequentially transferred and overlaid on the transfer material carried on the transfer material carrying member.
Claim 14
Dependent Claim
21 words
An apparatus according to claim 12, wherein said apparatus is capable of forming a full color image on the transfer material.
Claim 15
Dependent Claim
80 words
An image forming apparatus, comprising: an image bearing member; toner image forming means for forming a toner image on said image bearing member; transfer charging means for transferring the toner image from said image bearing member onto a transfer material; detecting means for detecting an electric current of said transfer charging means which is contributable to image transfer; and control means for controlling a toner charge amount before the image transfer in accordance with an output of said detecting means.
Claim 16
Dependent Claim
80 words
An image forming apparatus, comprising: an image bearing member; toner image forming means for forming a toner image on said image bearing member; transfer charging means for transferring the toner image from said image bearing member onto a transfer material; detecting means for detecting an electric current of said transfer charging means which is contributable to image transfer; and control means for controlling a toner charge amount before the image transfer in accordance with an output of said detecting means.
Claim 17
Dependent Claim
46 words
An apparatus according to claim 14, further comprising toner charging means for charging the toner image after formation of the toner image on said image bearing member and before the image transfer, and said control means controls the toner charge amount by the toner charging means.
Claim 18
Dependent Claim
40 words
An apparatus according to claim 14, further comprising a transfer material carrying member for carrying the transfer material wherein the toner image on said image bearing member is transferred onto the transfer material carried on said transfer material carrying member.
Claim 19
Dependent Claim
45 words
An apparatus according to claim 16, wherein said transfer charging means is contactable to such a side of the transfer material carrying member as is remote from said image bearing member, and said detecting means detects an electric current supplied to said transfer charging means.
Claim 20
Dependent Claim
25 words
An apparatus according to claim 17, wherein when said detecting means detects the electric currents, the transfer charging means is supplied with a constant voltage.
Claim 21
Dependent Claim
45 words
An apparatus according to claim 14, wherein said transfer charging means is in the form of a corona charging means having a wire electrode and a shield electrode, and wherein said detecting means detects electric currents flowing to the wire electrode and the shield electrode.
Claim 22
Dependent Claim
39 words
An apparatus according to claim 16, wherein plural color toner images can be formed on said image bearing member, and the toner images are sequentially transferred and overlaid on the transfer material carried on the transfer material carrying member.
Claim 23
Dependent Claim
21 words
An apparatus according to claim 20, wherein said apparatus is capable of forming a full color image on the transfer material.
References Cited (Backward Citations)
JPS5387739A
Cited
JPS57111570A
Cited
JPS5915272A
Cited
JPS5965866A
Cited
US4772918A
Cited
JPS6155675A
Cited
JPS62279367A
Cited
JPH03198079A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-03-21 | 1997-09-20 | 1998-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-03-21 | 2001-09-20 | 2002-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-03-21 | 2005-09-20 | 2006-03-22 | $7700.00 | Window Closed / Lapsed |