Patent US6173148B1 successfully refreshed from Google Patents.
US6173148B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image forming apparatus with a transfer member having an inherent volume resistance less than that of an inner layer of a transport support element
Assignee: Ricoh Co Ltd
•
Filing: 1999-02-12
•
Granted: 2001-01-09
•
Expires: 2019-02-12
Abstract
Abstract An image forming apparatus is provided with an image carrier that carries a visible image thereon, a transfer support element that conveys a sheet to which the visible image is transferred from the image carrier at a transfer nip portion, and a transfer member that applies a transfer bias to the transfer support element. The transfer member is in contact with an inner layer of the transfer support element at an edge of the transfer nip portion. The transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of the inner layer of the transfer support element. Further, a plurality of transfer members may be provided, in which case the transfer member closest to the transfer nip portion has the medium inherent volume resistance.
Inventors
- 👤 Itaru Matsuda
- 👤 Chiemi Kaneko
- 👤 Ryou Tanoue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:05
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/1665; G03G15/167; G03G15/1685; G03G2215/00; G03G2215/16; G03G2215/1604; G03G2215/1623
Claims Analysis
Total Claims: 54
Claim 1
Independent Claim
92 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a transfer member configured to apply a transfer bias to said transfer support element, said transfer member contacting an inner layer of said transfer support element at an edge of the transfer nip portion; and wherein said transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support element.
Claim 2
Dependent Claim
92 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a transfer member configured to apply a transfer bias to said transfer support element, said transfer member contacting an inner layer of said transfer support element at an edge of the transfer nip portion; and wherein said transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support element.
Claim 3
Dependent Claim
33 words
An image forming apparatus as claimed in claim 1 , wherein said inherent volume resistance of said transfer member is greater than 1×10 5 Ωcm inclusive, and is less than 1×10 9 Ωcm.
Claim 4
Dependent Claim
38 words
An image forming apparatus as claimed in claim 1 , wherein said inherent volume resistance of said inner layer of said transfer support element is greater than 1×10 7 Ωcm inclusive, and is less than 5×10 9 Ωcm.
Claim 5
Dependent Claim
38 words
An image forming apparatus as claimed in claim 3 , wherein said inherent volume resistance of an outer layer of said transfer support element is greater than 1×10 9 Ωcm inclusive, and is less than 1×10 13 Ωcm.
Claim 6
Dependent Claim
47 words
An image forming apparatus as claimed in claim 1 , wherein said transfer member is located below or downstream of said transfer nip portion where said transfer support element is in contact with said image carrier with respect to a moving direction of said transfer support element.
Claim 7
Dependent Claim
46 words
An image forming apparatus as claimed in claim 1 , further comprising a support member configured to contact said inner layer of said transfer support element, said support member located downstream of said transfer member with respect to a moving direction of said transfer support element.
Claim 8
Dependent Claim
38 words
An image forming apparatus as claimed in claim 6 , wherein a contact pressure between said transfer member and said transfer support element is less than a contact pressure between said support member and said transfer support element.
Claim 9
Dependent Claim
26 words
An image forming apparatus as claimed in claim 6 , wherein said support member is configured to apply said transfer bias to said transfer support element.
Claim 10
Dependent Claim
33 words
An image forming apparatus as claimed in claim 1 , wherein said transfer member comprises one element selected from the group consisting of a transfer roller, a transfer brush, and a transfer blade.
Claim 11
Dependent Claim
19 words
An image forming apparatus as claimed in claim 1 , wherein said transfer support element comprises a transfer belt.
Claim 12
Dependent Claim
18 words
An image forming apparatus as claimed in claim 1 , wherein said image carrier comprises a photoconductive belt.
Claim 13
Dependent Claim
20 words
An image forming apparatus as claimed in claim 1 , wherein said transfer support element comprises an intermediate transfer belt.
Claim 14
Dependent Claim
30 words
An image forming apparatus as claimed in claim 1 , wherein the transfer support element is an intermediate transfer belt onto which an image is transferred from said image carrier.
Claim 15
Dependent Claim
89 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support clement configured to contact said image carrier at a transfer nip portion; a plurality of transfer members configured to apply a transfer bias to said transfer support element, said plurality of transfer members contacting an inner layer of said transfer support element; wherein a nearest transfer member located at a nearest position to said transfer nip portion has a highest inherent volume resistance of all of said plurality of transfer members.
Claim 16
Dependent Claim
89 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support clement configured to contact said image carrier at a transfer nip portion; a plurality of transfer members configured to apply a transfer bias to said transfer support element, said plurality of transfer members contacting an inner layer of said transfer support element; wherein a nearest transfer member located at a nearest position to said transfer nip portion has a highest inherent volume resistance of all of said plurality of transfer members.
Claim 17
Dependent Claim
51 words
An image forming apparatus as claimed in claim 14 , wherein said inherent volume resistance corresponds to an inherent volume resistance between a point where said transfer bias is applied to said transfer support element and a point where said transfer support element is in contact with said nearest transfer member.
Claim 18
Dependent Claim
34 words
An image forming apparatus as claimed in claim 14 , wherein said inherent volume resistance of said nearest transfer member is greater than 1×10 5 Ωcm inclusive, and is less than 1×10 9 Ωcm.
Claim 19
Dependent Claim
38 words
An image forming apparatus as claimed in claim 14 , wherein said inherent volume resistance of said inner layer of said transfer support element is greater than 1×10 7 Ωcm inclusive, and is less than 5×10 9 Ωcm.
Claim 20
Dependent Claim
52 words
An image forming apparatus as claimed in claim 14 , wherein an electric resistance of a current flowing path between said nearest transfer member and said transfer nip portion is less than an electric resistances of all of current flowing paths between said plurality of transfer members and said transfer nip portion.
Claim 21
Dependent Claim
43 words
An image forming apparatus as claimed in claim 14 , wherein a contact pressure between said nearest transfer member and said transfer support element is a lowest of all of contact pressures between said plurality of transfer members and said transfer support element.
Claim 22
Dependent Claim
106 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a plurality of transfer members configured to apply a transfer bias to said transfer support element, said plurality of transfer members contacting an inner layer of said transfer support element; wherein an electric resistance of a current flowing path between a nearest of said plurality of transfer members to said transfer nip portion is a lowest of all of electric resistances of current flowing paths between said plurality of transfer members and said transfer nip portion.
Claim 23
Dependent Claim
106 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a plurality of transfer members configured to apply a transfer bias to said transfer support element, said plurality of transfer members contacting an inner layer of said transfer support element; wherein an electric resistance of a current flowing path between a nearest of said plurality of transfer members to said transfer nip portion is a lowest of all of electric resistances of current flowing paths between said plurality of transfer members and said transfer nip portion.
Claim 24
Dependent Claim
43 words
The image forming apparatus as claimed in claim 20 , wherein a contact pressure between the nearest transfer member and the transfer support element is a lowest of all of contact pressures between the plurality of transfer members and the transfer support element.
Claim 25
Dependent Claim
100 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a plurality of transfer members configured to apply a transfer bias to said transfer support element, said plurality of transfer members contacting an inner layer of said transfer support element; and wherein a contact pressure between a nearest transfer member located nearest to said transfer nip and the transfer support element is a lowest of all of contact pressures between said plurality of transfer members and said transfer support element.
Claim 26
Dependent Claim
100 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a plurality of transfer members configured to apply a transfer bias to said transfer support element, said plurality of transfer members contacting an inner layer of said transfer support element; and wherein a contact pressure between a nearest transfer member located nearest to said transfer nip and the transfer support element is a lowest of all of contact pressures between said plurality of transfer members and said transfer support element.
Claim 27
Dependent Claim
52 words
The image forming apparatus as claimed in claim 22 , wherein an electric resistance of a current flowing path between the nearest transfer member to said transfer nip portion is a lowest of all of electric resistances of current flowing paths between said plurality of transfer members and said transfer nip portion.
Claim 28
Dependent Claim
88 words
An image forming apparatus comprising: image carrier means for carrying a visible image thereon; transfer support means for contacting said image carrier means at a transfer nip portion; transfer means for applying a transfer bias to said transfer support means, said transfer means contacting an inner layer of said transfer support means at an edge of the transfer nip portion; and wherein said transfer means has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support means.
Claim 29
Dependent Claim
88 words
An image forming apparatus comprising: image carrier means for carrying a visible image thereon; transfer support means for contacting said image carrier means at a transfer nip portion; transfer means for applying a transfer bias to said transfer support means, said transfer means contacting an inner layer of said transfer support means at an edge of the transfer nip portion; and wherein said transfer means has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support means.
Claim 30
Dependent Claim
29 words
An image forming apparatus as claimed in claim 24 , further comprising support means contacting said inner layer of said transfer support means for supporting said transfer support means.
Claim 31
Dependent Claim
36 words
An image forming apparatus as claimed in claim 24 , wherein said transfer means includes a plurality of transfer elements, and a transfer element nearest to the transfer nip portion has the medium inherent volume resistance.
Claim 32
Dependent Claim
146 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a transfer member configured to apply a transfer bias to said transfer support element, said transfer member contacting an inner layer of said transfer support element; a support member configured to contact said inner layer of said transfer support element, said support member located downstream of said transfer member with respect to a moving direction of said transfer support element; wherein said transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support element; and wherein a contact pressure between said transfer member and said transfer support element is less than a contact pressure between said support member and said transfer support element.
Claim 33
Dependent Claim
146 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a transfer member configured to apply a transfer bias to said transfer support element, said transfer member contacting an inner layer of said transfer support element; a support member configured to contact said inner layer of said transfer support element, said support member located downstream of said transfer member with respect to a moving direction of said transfer support element; wherein said transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support element; and wherein a contact pressure between said transfer member and said transfer support element is less than a contact pressure between said support member and said transfer support element.
Claim 34
Dependent Claim
33 words
An image forming apparatus as claimed in claim 27 , wherein said inherent volume resistance of said transfer member is greater than 1×10 5 Ωcm inclusive, and is less than 1×10 9 Ωcm.
Claim 35
Dependent Claim
38 words
An image forming apparatus as claimed in claim 27 , wherein said inherent volume resistance of said inner layer of said transfer support element is greater than 1×10 7 Ωcm inclusive, and is less than 5×10 9 Ωcm.
Claim 36
Dependent Claim
38 words
An image forming apparatus as claimed in claim 29 , wherein said inherent volume resistance of an outer layer of said transfer support element is greater than 1×10 9 Ωcm inclusive, and is less than 1×10 13 Ωcm.
Claim 37
Dependent Claim
47 words
An image forming apparatus as claimed in claim 27 , wherein said transfer member is located below or downstream of said transfer nip portion where said transfer support element is in contact with said image carrier with respect to a moving direction of said transfer support element.
Claim 38
Dependent Claim
26 words
An image forming apparatus as claimed in claim 27 , wherein said support member is configured to apply said transfer bias to said transfer support element.
Claim 39
Dependent Claim
33 words
An image forming apparatus as claimed in claim 27 , wherein said transfer member comprises one element selected from the group consisting of a transfer roller, a transfer brush, and a transfer blade.
Claim 40
Dependent Claim
19 words
An image forming apparatus as claimed in claim 27 , wherein said transfer support element comprises a transfer belt.
Claim 41
Dependent Claim
18 words
An image forming apparatus as claimed in claim 27 , wherein said image carrier comprises a photoconductive belt.
Claim 42
Dependent Claim
20 words
An image forming apparatus as claimed in claim 27 , wherein said transfer support element comprises an intermediate transfer belt.
Claim 43
Dependent Claim
30 words
An image forming apparatus as claimed in claim 27 , wherein the transfer support element is an intermediate transfer belt onto which an image is transferred from said image carrier.
Claim 44
Dependent Claim
134 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a transfer member configured to apply a transfer bias to said transfer support element, said transfer member contacting an inner layer of said transfer support element; a support member configured to contact said inner layer of said transfer support element, said support member located downstream of said transfer member with respect to a moving direction of said transfer support element; wherein said transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support element; and wherein said support member is configured to apply said transfer bias to said transfer support element.
Claim 45
Dependent Claim
134 words
An image forming apparatus comprising: an image carrier configured to carry a visible image thereon; a transfer support element configured to contact said image carrier at a transfer nip portion; a transfer member configured to apply a transfer bias to said transfer support element, said transfer member contacting an inner layer of said transfer support element; a support member configured to contact said inner layer of said transfer support element, said support member located downstream of said transfer member with respect to a moving direction of said transfer support element; wherein said transfer member has a medium inherent volume resistance which is less than an inherent volume resistance of said inner layer of said transport support element; and wherein said support member is configured to apply said transfer bias to said transfer support element.
Claim 46
Dependent Claim
33 words
An image forming apparatus as claimed in claim 38 , wherein said inherent volume resistance of said transfer member is greater than 1×10 5 Ωcm inclusive, and is less than 1×10 9 Ωcm.
Claim 47
Dependent Claim
38 words
An image forming apparatus as claimed in claim 38 , wherein said inherent volume resistance of said inner layer of said transfer support element is greater than 1×10 7 Ωcm inclusive, and is less than 5×10 9 Ωcm.
Claim 48
Dependent Claim
38 words
An image forming apparatus as claimed in claim 40 , wherein said inherent volume resistance of an outer layer of said transfer support element is greater than 1×10 9 Ωcm inclusive, and is less than 1×10 13 Ωcm.
Claim 49
Dependent Claim
47 words
An image forming apparatus as claimed in claim 38 , wherein said transfer member is located below or downstream of said transfer nip portion where said transfer support element is in contact with said image carrier with respect to a moving direction of said transfer support element.
Claim 50
Dependent Claim
33 words
An image forming apparatus as claimed in claim 38 , wherein said transfer member comprises one element selected from the group consisting of a transfer roller, a transfer brush, and a transfer blade.
Claim 51
Dependent Claim
19 words
An image forming apparatus as claimed in claim 38 , wherein said transfer support element comprises a transfer belt.
Claim 52
Dependent Claim
18 words
An image forming apparatus as claimed in claim 38 , wherein said image carrier comprises a photoconductive belt.
Claim 53
Dependent Claim
20 words
An image forming apparatus as claimed in claim 38 , wherein said transfer support element comprises an intermediate transfer belt.
Claim 54
Dependent Claim
30 words
An image forming apparatus as claimed in claim 38 , wherein the transfer support element is an intermediate transfer belt onto which an image is transferred from said image carrier.
References Cited (Backward Citations)
US5189479A
Cited
US5557384A
Cited
US5666622A
Cited
US5461461A
Cited
US5659843A
Cited
US5640660A
Cited
US5495317A
Cited
US5406360A
Cited
US5552871A
Cited
US5572304A
Cited
US5515146A
Cited
US5655200A
Cited
US5812919A
Cited
US5832351A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-01-09 | 2004-07-10 | 2005-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-01-09 | 2008-07-10 | 2009-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-01-09 | 2012-07-10 | 2013-01-09 | $7700.00 | Window Closed / Lapsed |