Patent US6920294B2 successfully refreshed from Google Patents.
US6920294B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image forming apparatus
Assignee: Toshiba Corp
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Filing: 2004-06-03
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Granted: 2005-07-19
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Expires: 2024-06-03
Abstract
Abstract An image fanning apparatus is provided with a pressing roller for pressing a sheet at the time of a fixing operation; a fixing roller having a hollow portion, facing the pressing roller, rising in temperature by being heated, and fixing a developer to the sheet by sandwiching the sheet between the fixing roller and the pressing roller; and induction heating coils including a center-section coil and an end-section coil, and arranged inside the fixing roller in an axial direction so as to leave a space between the center-section coil and the end-section coil, the space being adjusted so that the temperature of one surface of the fixing roller, the one surface opposing the space, is not higher than the temperatures of the other surface of the fixing roller, the other surface opposing central portions of the coils.
Inventors
- 👤 Kenji Takano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:02
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2039; G03G15/2042; H; H05; H05B; H05B6/00; H05B6/02; H05B6/10; H05B6/14; H05B6/145
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
143 words
A heating apparatus comprising: a beat roller rotating around a rotation axis; a press roller generating a predetermined pressure with the heat roller; a first coil heating the heat roller by induction heating; a second coil located in parallel to the rotation axis so as to be adjacent to the first coil with a predetermined space therebetween, the second coil heating the heat roller by induction heating; a first drive circuit driving the first coil; and a second drive circuit driving the second coil, wherein when the first and second drive circuits are driven, one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the first coil in a direction parallel to the rotation axis, and wherein the first and second drive circuits alternately drive the first and second coils.
Claim 2
Dependent Claim
143 words
A heating apparatus comprising: a beat roller rotating around a rotation axis; a press roller generating a predetermined pressure with the heat roller; a first coil heating the heat roller by induction heating; a second coil located in parallel to the rotation axis so as to be adjacent to the first coil with a predetermined space therebetween, the second coil heating the heat roller by induction heating; a first drive circuit driving the first coil; and a second drive circuit driving the second coil, wherein when the first and second drive circuits are driven, one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the first coil in a direction parallel to the rotation axis, and wherein the first and second drive circuits alternately drive the first and second coils.
Claim 3
Dependent Claim
41 words
The heating apparatus according to claim 1 , further comprising an overheating prevention device located around the one of peak positions, the overheating prevention device detecting whether the surface temperature of the heat roller is at an abnormal value or not.
Claim 4
Dependent Claim
36 words
The heating apparatus according to claim 2 , wherein when the overheating prevention device detects that the surface temperature of the heat roller is at an abnormal value, the first and second drive circuits are stopped.
Claim 5
Dependent Claim
53 words
The heating apparatus according to claim 1 , wherein when the first and second drive circuits are driven, the one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the second coil in a direction parallel to the rotation axis.
Claim 6
Dependent Claim
172 words
An image forming apparatus comprising: an image forming unit forming a toner image on paper; a heat roller rotating around a rotation axis; a press roller generating a predetermined pressure with the heat roller, so as to fix the toner image on the paper with heat and pressure; a first coil heating the heat roller by induction heating; a second coil located in parallel to the rotation axis so as to be adjacent to the first coil with a predetermined space therebetween, the second coil heating the heat roller by induction heating; a first drive circuit driving the first coil; and a second drive circuit driving the second coil, wherein when the first and second drive circuits drive the first and second coils, one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the first coil in a direction parallel to the rotation axis, and wherein the first and second drive circuits alternately drive the first and second coils.
Claim 7
Dependent Claim
172 words
An image forming apparatus comprising: an image forming unit forming a toner image on paper; a heat roller rotating around a rotation axis; a press roller generating a predetermined pressure with the heat roller, so as to fix the toner image on the paper with heat and pressure; a first coil heating the heat roller by induction heating; a second coil located in parallel to the rotation axis so as to be adjacent to the first coil with a predetermined space therebetween, the second coil heating the heat roller by induction heating; a first drive circuit driving the first coil; and a second drive circuit driving the second coil, wherein when the first and second drive circuits drive the first and second coils, one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the first coil in a direction parallel to the rotation axis, and wherein the first and second drive circuits alternately drive the first and second coils.
Claim 8
Dependent Claim
42 words
The image forming apparatus according to claim 5 , further comprising an overheating prevention device located around the one of peak positions, the overheating prevention device detecting whether the surface temperature of the heat roller is at an abnormal value or not.
Claim 9
Dependent Claim
37 words
The image forming apparatus according to claim 6 , wherein when the overheating prevention device detects that the surface temperature of the heat roller is at an abnormal value, the first and second drive circuits are stopped.
Claim 10
Dependent Claim
54 words
The image forming apparatus according to claim 5 , wherein when the first and second drive circuits are driven, the one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the second coil in a direction parallel to the rotation axis.
Claim 11
Dependent Claim
32 words
The image forming apparatus according to claim 5 , further comprising: a first control circuit controlling the first and second drive circuits; and a second control circuit controlling the image forming apparatus.
Claim 12
Dependent Claim
38 words
The image forming apparatus according to claim 9 , further comprising a temperature detecting device detecting surface temperature of the heat roller, wherein a detection result of the temperature detecting device is inputted to the second control circuit.
Claim 13
Dependent Claim
199 words
An image forming apparatus comprising: an image forming unit forming a toner image on paper; a heat roller rotating around a rotation axis; a press roller generating a predetermined pressure with the heat roller, so as to fix the toner image on the paper with heat and pressure; a first coil heating the heat roller by induction heating; a second coil located in parallel to the rotation axis so as to be adjacent to the first coil with a predetermined space therebetween, the second coil heating the heat roller by induction heating; a first drive circuit driving the first coil; and a second drive circuit driving the second coil, wherein when the first and second drive circuits drive the first and second coils, one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the first coil in a direction parallel to the rotation axis, and wherein the space between the first coil and the second coil are set in the range of from 10 to 20 mm in a roller axis direction, a lowest temperature position being set to be between the first and second coils.
Claim 14
Dependent Claim
199 words
An image forming apparatus comprising: an image forming unit forming a toner image on paper; a heat roller rotating around a rotation axis; a press roller generating a predetermined pressure with the heat roller, so as to fix the toner image on the paper with heat and pressure; a first coil heating the heat roller by induction heating; a second coil located in parallel to the rotation axis so as to be adjacent to the first coil with a predetermined space therebetween, the second coil heating the heat roller by induction heating; a first drive circuit driving the first coil; and a second drive circuit driving the second coil, wherein when the first and second drive circuits drive the first and second coils, one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the first coil in a direction parallel to the rotation axis, and wherein the space between the first coil and the second coil are set in the range of from 10 to 20 mm in a roller axis direction, a lowest temperature position being set to be between the first and second coils.
Claim 15
Dependent Claim
42 words
The image forming apparatus according to claim 11 , further comprising an overheating prevention device located around the one of peak positions, the overheating prevention device detecting whether the surface temperature of the heat roller is at an abnormal value or not.
Claim 16
Dependent Claim
37 words
The image forming apparatus according to claim 12 , wherein when the overheating prevention device detects that the surface temperature of the heat roller is at an abnormal value, the first and second drive circuits are stopped.
Claim 17
Dependent Claim
54 words
The image forming apparatus according to claim 11 , wherein when the first and second drive circuits are driven, the one of peak positions of surface temperature of the heat roller is set to be around a central portion of a width of the second coil in a direction parallel to the rotation axis.
Claim 18
Dependent Claim
23 words
The image forming apparatus according to claim 11 , wherein the first and second drive circuits alternately drive the first and second coils.
Claim 19
Dependent Claim
32 words
The image forming apparatus according to claim 11 , further comprising: a first control circuit controlling the first and second drive circuits; and a second control circuit controlling the image forming apparatus.
Claim 20
Dependent Claim
38 words
The image forming apparatus according to claim 16 , further comprising: a temperature detecting device detecting surface temperature of the heat roller, wherein a detection result of the temperature detecting device is inputted to the second control circuit.
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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) | 2008-07-18 | 2009-01-17 | 2009-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2012-07-18 | 2013-01-17 | 2013-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2016-07-18 | 2017-01-17 | 2017-07-19 | $7700.00 | Window Closed / Lapsed |