US4570044A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Induction heating and fixing device for a copying machine
Assignee: Sharp Corp
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Filing: 1983-04-19
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Granted: 1986-02-11
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Expires: 2003-04-19
Abstract
Abstract An induction heating and fixing device suitable for a copying machine comprises a fixing roller, a first iron core, a second iron core, and two third iron cores. The first iron core inserted into the center of the fixing roller. The first, the second, and the third iron cores are magnetically and mechanically combined together to form a closed magnetic circuit. Magnetic blocks are provided for combining the first, the second, and the third iron cores. Each of these iron cores comprises a plurality of isolated thin silicon steel plates. At least one of the two of the third iron cores is disassembled to remove the fixing roller from the device for maintenance.
Inventors
- 👤 Toshiaki Kobayashi
- 👤 Noriaki Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:07
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2064
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
152 words
An induction heating and fixing device suitable for a copying machine comprising in combination at least one fixing roller for fixing a tone image onto a copy paper, said fixing roller having an electro-conductive surface; a first iron core means with respective ends inserted into a center of said at least one fixing roller comprising a coil means wound around said first iron core means; a second iron core means positioned over said fixing roller substantially parallel to said first core means and having corresponding ends; a set of third iron core means interposed between said respective ends of said first and second iron core means, said first, second and third iron core means being magnetically and mechanically connected to form a closed magnetic circuit around said fixing roller for induction heating of said surface of said fixing roller, said mechanical connection being such that said iron cores may be readily disassembled.
Claim 2
Dependent Claim
152 words
An induction heating and fixing device suitable for a copying machine comprising in combination at least one fixing roller for fixing a tone image onto a copy paper, said fixing roller having an electro-conductive surface; a first iron core means with respective ends inserted into a center of said at least one fixing roller comprising a coil means wound around said first iron core means; a second iron core means positioned over said fixing roller substantially parallel to said first core means and having corresponding ends; a set of third iron core means interposed between said respective ends of said first and second iron core means, said first, second and third iron core means being magnetically and mechanically connected to form a closed magnetic circuit around said fixing roller for induction heating of said surface of said fixing roller, said mechanical connection being such that said iron cores may be readily disassembled.
Claim 3
Dependent Claim
23 words
The device of claim 1, further comprising three magnetic block means for magnetically and mechanically combining said first, second, and third iron core.
Claim 4
Dependent Claim
23 words
The device of claim 1, wherein said first, second, and third iron core means comprise a plurality of insulated thin silicon steel plates.
Claim 5
Dependent Claim
15 words
The device of claim 1, wherein said fixing roller is coated with a synthetic resin.
Claim 6
Dependent Claim
11 words
The device of claim 4, wherein said synthetic resin is Teflon.
Claim 7
Dependent Claim
19 words
The device of claim 1, wherein said first, second, and third iron core means are combined by screw means.
Claim 8
Dependent Claim
41 words
The device of claim 1, wherein said second iron core means has a height less than that of said first iron core means, and said second iron core means has a width greater than that of said first iron core means.
Claim 9
Dependent Claim
99 words
The device of claim 1, including a power source for said coil means, wherein said coil means comprises a first wiring and a second wiring, with a switch means provided for switching between said first and second wirings, the number of turns of said first wiring being greater than the number of turns of said second wiring, whereby said power source is connected to said second wiring via said switch means until said roller surface reaches said fixing temperature at which time said switch means is switched to said first wiring to reduce power consumed by said fixing device.
Claim 10
Dependent Claim
46 words
The device of claim 1, further comprising at least one block member inserted into at least a part of said respective ends of said first iron core, said at least one block member having an aperture therein for combining said first and third iron core means.
Claim 11
Dependent Claim
24 words
The device of claim 3, further comprising opening means in said first iron core means for combining the plurality of insulated thin plates together.
Claim 12
Dependent Claim
36 words
The device of claim 8, further including a temperature sensor for sensing the temperature of the surface of said fixing roller which enables switching of said switch means between said second wiring and said first wiring.
References Cited (Backward Citations)
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Cited
US4229644A
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US4329565A
Cited
US4435072A
Cited
US4456368A
Cited
US4365139A
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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) | 1989-02-10 | 1989-08-12 | 1990-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-10 | 1993-08-12 | 1994-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-10 | 1997-08-12 | 1998-02-11 | $7700.00 | Window Closed / Lapsed |