US4891495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature control device for heat-roll fusing apparatus
Assignee: Minolta Co Ltd
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Filing: 1988-09-22
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Granted: 1990-01-02
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Expires: 2008-09-22
Abstract
Abstract A temperature control device adapted to increase the roll surface temperature to the fusing temperature after initiation of power supply. When the roll surface temperature is to be increased from a level below a reference temperature, the current is supplied until the roll surface temperature reaches a predetermined temperature lower than the fusing temperature, and when the roll surface temperature is to be increased from a level higher than the reference temperature, the current is supplied for a predetermined time which is set according to the roll surface temperature at the initiation of power supply.
Inventors
- 👤 Kazuhiro Araki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:03
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2039
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
149 words
A temperature control device for a heat roll fusing apparatus including a heat roll having a heating element therein, a pressure roll in contact with said heat roll and a sensing element for sensing a fusing temperature, said temperature control device comprising: detecting means for detecting an initial temperature at initiation of power supplying; and temperature control means for supplying a current to the heating element so as to warm up the heat roll to a fixing temperature and operable in a first mode when the intial temperature is lower than a reference temperature and in a second mode when the initial temperature is higher than the reference temperature, wherein the current is supplied in the first mode until a time when the sensing element senses a predetermined temperature which is lower than the fixing temperature, whereas the current is supplied in the second mode during a predetermined time.
Claim 2
Dependent Claim
149 words
A temperature control device for a heat roll fusing apparatus including a heat roll having a heating element therein, a pressure roll in contact with said heat roll and a sensing element for sensing a fusing temperature, said temperature control device comprising: detecting means for detecting an initial temperature at initiation of power supplying; and temperature control means for supplying a current to the heating element so as to warm up the heat roll to a fixing temperature and operable in a first mode when the intial temperature is lower than a reference temperature and in a second mode when the initial temperature is higher than the reference temperature, wherein the current is supplied in the first mode until a time when the sensing element senses a predetermined temperature which is lower than the fixing temperature, whereas the current is supplied in the second mode during a predetermined time.
Claim 3
Dependent Claim
32 words
A temperature control device for a heat roll fusing apparatus as claimed in claim 1 wherein said predetermined time corresponds to a temperature range between the reference temperature and the fixing temperature.
Claim 4
Dependent Claim
28 words
A temperature control device for a heat roll fusing apparatus as claimed in claim 1, wherein said predetermined time is determined by calculation based on the initial temperature.
Claim 5
Dependent Claim
25 words
A temperature control device for a heat roll fusing apparatus as claimed in claim 1, wherein said reference temperature is lower than the fixing temperature.
Claim 6
Dependent Claim
172 words
A temperature control device for a heat roll fusing apparatus including a heat roll having a heating element therein, a pressure roll in contact with said heat roll, a sensing element for sensing a fusing temperature and a temperature maintaining means for maintaining said fusing temperature at a fixing temperature, said temperature control device comprising: temperature control means for supplying a current to the heating element so as to warm up the heat roll to a fixing temperature and operable in a first mode when the initial temperature is lower than a reference temperature and in a second mode when the initial temperature is higher than the reference temperature, wherein the current is supplied in the first mode until a time when the sensing element senses a predetermined temperature which is lower than the fixing temperature, whereas the current is supplied in the second mode during a predetermined time; and prohibiting means for prohibiting operation of the temperature maintaining means when the heat is at a lower temperature than the fixing temperature.
Claim 7
Dependent Claim
172 words
A temperature control device for a heat roll fusing apparatus including a heat roll having a heating element therein, a pressure roll in contact with said heat roll, a sensing element for sensing a fusing temperature and a temperature maintaining means for maintaining said fusing temperature at a fixing temperature, said temperature control device comprising: temperature control means for supplying a current to the heating element so as to warm up the heat roll to a fixing temperature and operable in a first mode when the initial temperature is lower than a reference temperature and in a second mode when the initial temperature is higher than the reference temperature, wherein the current is supplied in the first mode until a time when the sensing element senses a predetermined temperature which is lower than the fixing temperature, whereas the current is supplied in the second mode during a predetermined time; and prohibiting means for prohibiting operation of the temperature maintaining means when the heat is at a lower temperature than the fixing temperature.
Claim 8
Dependent Claim
25 words
A temperature control device for a heat roll fusing apparatus as claimed in claim 5, wherein said reference temperature is lower that the fixing temperature.
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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) | 1993-01-01 | 1993-07-03 | 1994-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-01 | 1997-07-03 | 1998-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-01 | 2001-07-03 | 2002-01-02 | $7700.00 | Window Closed / Lapsed |