Patent US5365314A successfully refreshed from Google Patents.
US5365314A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image heating apparatus capable of changing duty ratio
Assignee: Canon Inc
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Filing: 1993-03-29
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Granted: 1994-11-15
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Expires: 2013-03-29
Abstract
Abstract An image heating apparatus includes a heater; a temperature detecting member for detecting a temperature of the heater; the controller for controlling electric power supplied to the heater so that the temperature detected by the temperature detecting member is maintained at a predetermined temperature; comparing device for comparing the temperature detected by the temperature detecting member to the reference temperature; wherein, when the detected temperature remains to be no less than the reference temperature for a predetermined period of time, the controller reduces a duty ratio of the electric power to be supplied to the heater.
Inventors
- 👤 Kouichi Okuda
- 👤 Shunji Nakamura
- 👤 Yasumasa Ohtsuka
- 👤 Yohji Tomoyuki
- 👤 Akira Hayakawa
- 👤 Daizo Fukuzawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:02
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2039; G03G15/205
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
126 words
An image heating apparatus comprising: a heater; a temperature detecting member for detecting a temperature of said heater; controlling means for controlling electric power supplied to said heater so that the temperature detected by said temperature detecting member is maintained at a predetermined temperature; and comparing means for comparing the temperature detected by said temperature detecting member to a reference temperature higher than the predetermined temperature; wherein when said detected temperature exceeds said reference temperature, said control means reduces a duty ratio of the electric power to be supplied to said heater; and after a predetermined period of time, when said detected temperature still exceeds the reference temperature, said control means further reduces the duty ratio of the electric power to be supplied to said heater.
Claim 2
Dependent Claim
126 words
An image heating apparatus comprising: a heater; a temperature detecting member for detecting a temperature of said heater; controlling means for controlling electric power supplied to said heater so that the temperature detected by said temperature detecting member is maintained at a predetermined temperature; and comparing means for comparing the temperature detected by said temperature detecting member to a reference temperature higher than the predetermined temperature; wherein when said detected temperature exceeds said reference temperature, said control means reduces a duty ratio of the electric power to be supplied to said heater; and after a predetermined period of time, when said detected temperature still exceeds the reference temperature, said control means further reduces the duty ratio of the electric power to be supplied to said heater.
Claim 3
Dependent Claim
41 words
An image heating apparatus according to claim 1 further comprising a film sliding on said heater, wherein said heater is used in static condition, and an image on the recording material is heated by heat from said heater through said film.
Claim 4
Dependent Claim
27 words
An image heating apparatus according to claim 2 further comprising a backup member forming a nip with said heater, with said film being interposed in the nip.
Claim 5
Dependent Claim
128 words
An image heating apparatus comprising: a heater; a temperature detecting member for detecting the temperature of said heater; controlling means for controlling the electric power supplied to said heater so that the temperature detected by said temperature detecting member is maintained at a predetermined temperature; comparing means for comparing the temperature detected by said temperature detecting member to a reference temperature lower than the predetermined temperature; wherein when said detected temperature drops below said reference temperature, said controlling means increases a duty ratio of the electric power to be supplied to said heater; and after a predetermined period of time, when said detected temperature still remains below the reference temperature, said controlling means further increases the duty ratio of the electric power to be supplied to said heater.
Claim 6
Dependent Claim
128 words
An image heating apparatus comprising: a heater; a temperature detecting member for detecting the temperature of said heater; controlling means for controlling the electric power supplied to said heater so that the temperature detected by said temperature detecting member is maintained at a predetermined temperature; comparing means for comparing the temperature detected by said temperature detecting member to a reference temperature lower than the predetermined temperature; wherein when said detected temperature drops below said reference temperature, said controlling means increases a duty ratio of the electric power to be supplied to said heater; and after a predetermined period of time, when said detected temperature still remains below the reference temperature, said controlling means further increases the duty ratio of the electric power to be supplied to said heater.
Claim 7
Dependent Claim
41 words
An image heating apparatus according to claim 4 further comprising a film sliding on said heater, wherein said heater is used in static condition, and an image on the recording material is heated by heat from said heater through said film.
Claim 8
Dependent Claim
27 words
An image heating apparatus according to claim 5 further comprising a backup member forming a nip with said heater, with said film being interposed in the nip.
Claim 9
Dependent Claim
119 words
An image heating apparatus comprising: a heater; a temperature detecting means for detecting a temperature of said heater; control means for controlling electric power supply to said heater so as to maintain detection of a predetermined temperature by said temperature detecting means during an image heating operation; a plurality of tables for use by said control means to provide electric power supply levels for a plurality of temperature ranges; comparison means for comparing the temperature detected by said temperature detecting means with a reference temperature; wherein said control means changes the table to be used by said control means when the temperature detected by said temperature detecting means is higher than the reference temperature for a predetermined time period.
Claim 10
Dependent Claim
119 words
An image heating apparatus comprising: a heater; a temperature detecting means for detecting a temperature of said heater; control means for controlling electric power supply to said heater so as to maintain detection of a predetermined temperature by said temperature detecting means during an image heating operation; a plurality of tables for use by said control means to provide electric power supply levels for a plurality of temperature ranges; comparison means for comparing the temperature detected by said temperature detecting means with a reference temperature; wherein said control means changes the table to be used by said control means when the temperature detected by said temperature detecting means is higher than the reference temperature for a predetermined time period.
Claim 11
Dependent Claim
41 words
An apparatus according to claim 7, wherein said control means changes the table so that the electric power supply is reduced when the temperature detected by said temperature detecting means is higher than the reference temperature for a predetermined time period.
Claim 12
Dependent Claim
19 words
An image heating apparatus according to claim 7, wherein said reference temperature is the same as said predetermined temperature.
Claim 13
Dependent Claim
41 words
An image heating apparatus according to claim 7, further comprising a film sliding on said heater, wherein said heater is used in static condition, and an image on the recording material is heated by heat from said heater through said film.
Claim 14
Dependent Claim
27 words
An image heating apparatus according to claim 10, further comprising a backup member forming a nip with said heater, with said film being interposed in the nip.
Claim 15
Dependent Claim
119 words
An image heating apparatus comprising: a heater; a temperature detecting means for detecting a temperature of said heater; control means for controlling electric power supply to said heater so as to maintain detection of a predetermined temperature by said temperature detecting means during an image heating operation; a plurality of tables for use by said control means to provide electric power supply levels for a plurality of temperature ranges; comparison means for comparing the temperature detected by said temperature detecting means with a reference temperature; wherein said control means changes the table to be used by said control means when the temperature detected by said temperature detecting means is lower than the reference temperature for a predetermined time period.
Claim 16
Dependent Claim
119 words
An image heating apparatus comprising: a heater; a temperature detecting means for detecting a temperature of said heater; control means for controlling electric power supply to said heater so as to maintain detection of a predetermined temperature by said temperature detecting means during an image heating operation; a plurality of tables for use by said control means to provide electric power supply levels for a plurality of temperature ranges; comparison means for comparing the temperature detected by said temperature detecting means with a reference temperature; wherein said control means changes the table to be used by said control means when the temperature detected by said temperature detecting means is lower than the reference temperature for a predetermined time period.
Claim 17
Dependent Claim
41 words
An apparatus according to claim 12, wherein said control means changes the table so that the electric power supply is increased when the temperature detected by said temperature detecting means is lower than the reference temperature for a predetermined time period.
Claim 18
Dependent Claim
19 words
An image heating apparatus according to claim 12, wherein said reference temperature is the same as said predetermined temperature.
Claim 19
Dependent Claim
41 words
An image heating apparatus according to claim 12, further comprising a film sliding on said heater, wherein said heater is used in static condition, and an image on the recording material is heated by heat from said heater through said film.
Claim 20
Dependent Claim
27 words
An image heating apparatus according to claim 15, further comprising a backup member forming a nip with said heater, with said film being interposed in the nip.
References Cited (Backward Citations)
US4496829A
Cited
US5149941A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-14 | 1998-05-16 | 1998-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-14 | 2002-05-16 | 2002-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-14 | 2006-05-16 | 2006-11-15 | $7700.00 | Window Closed / Lapsed |