US5343019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image forming apparatus coping with power supply voltage drift
Assignee: Canon Inc
•
Filing: 1993-02-25
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Granted: 1994-08-30
•
Expires: 2013-02-25
Abstract
Abstract An image forming apparatus includes a fixing heater driven by a voltage supplied from a commercial power supply, a transformer for transforming the voltage supplied from the commercial power supply into a predetermined voltage, and supplying the predetermined voltage to a load in the apparatus, and a controller for detecting the voltage transformed by the transformer, and controlling energization to the fixing heater.
Inventors
- 👤 Yasumasa Nashida
- 👤 Toshio Yoshimoto
- 👤 Yasuhiro Nakata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:11
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/33561; G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; H02M3/33507; H02M1/00; H02M1/0003; H02M1/0032; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
129 words
An image forming apparatus comprising: image forming means for forming an unfixed image on a record medium; fixing means for heating and fixing the unfixed image on the record medium, said fixing means including a fixing heater driven by a voltage supplied from a commercial power supply; alternating to direct current converting means for converting an alternating voltage from the commercial power supply into direct voltage of a predetermined value, said alternating to direct current converting means including a transformer for transforming the voltage from the commercial power supply into the direct voltage; a semiconductor element driven by the direct voltage converted by said alternating to direct current converting means; and digital control means for detecting the voltage transformed by said transformer to control energization to said fixing heater.
Claim 2
Dependent Claim
129 words
An image forming apparatus comprising: image forming means for forming an unfixed image on a record medium; fixing means for heating and fixing the unfixed image on the record medium, said fixing means including a fixing heater driven by a voltage supplied from a commercial power supply; alternating to direct current converting means for converting an alternating voltage from the commercial power supply into direct voltage of a predetermined value, said alternating to direct current converting means including a transformer for transforming the voltage from the commercial power supply into the direct voltage; a semiconductor element driven by the direct voltage converted by said alternating to direct current converting means; and digital control means for detecting the voltage transformed by said transformer to control energization to said fixing heater.
Claim 3
Dependent Claim
35 words
An apparatus according to claim 1, wherein the secondary winding of said transformer comprises a main coil for supplying the voltage to a load in said apparatus, and an auxiliary coil for detecting the voltage.
Claim 4
Dependent Claim
48 words
An apparatus according to claim 1, further comprising a heating member heated by said fixing heater, and a temperature detection member for detecting a temperature of said heating member, wherein said digital control means controls energization on the basis of a detection output from said temperature detection member.
Claim 5
Dependent Claim
26 words
An apparatus according to claim 1, wherein said control means comprises calculation means for controlling voltage on the basis of a used current of the load.
Claim 6
Dependent Claim
26 words
An apparatus according to claim 1, wherein said control means comprises a table for controlling voltage on the basis of a used current of the load.
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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) | 1997-08-29 | 1998-02-28 | 1998-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-29 | 2002-02-28 | 2002-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-29 | 2006-02-28 | 2006-08-30 | $7700.00 | Window Closed / Lapsed |