US4544828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heating device
Assignee: Canon Inc
•
Filing: 1983-08-15
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Granted: 1985-10-01
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Expires: 2003-08-15
Abstract
Abstract A heating device for heating an object with a heating element composed of ceramic particles having a positive temperature coefficient of resistance dispersed in a binder.
Inventors
- 👤 Michio Shigenobu
- 👤 Hiroshi Satomura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:24
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/10; H05B3/12; H05B3/14; H05B3/141; G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2053; H01; H01C; H01C7/00; H01C7/02; H01C7/027; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49085
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
101 words
A heating device comprising: a heat generating element including a non-organic binder having dispersed therein and in electrically contacting state ceramic particles which have PTC characteristics, said element being formed by pulverizing ceramic sintered so as to have PTC characteristics, dispersing said PTC particles in said binder, and being incorporated at a temperature lower than the sintering temperature so as integrally to form the element while retaining the binder therein; and electrical means for applying a voltage across said heat generating element to cause heat generation without dissipation of the binder, wherein said heating device provides a substantially uniform heat distribution.
Claim 2
Dependent Claim
101 words
A heating device comprising: a heat generating element including a non-organic binder having dispersed therein and in electrically contacting state ceramic particles which have PTC characteristics, said element being formed by pulverizing ceramic sintered so as to have PTC characteristics, dispersing said PTC particles in said binder, and being incorporated at a temperature lower than the sintering temperature so as integrally to form the element while retaining the binder therein; and electrical means for applying a voltage across said heat generating element to cause heat generation without dissipation of the binder, wherein said heating device provides a substantially uniform heat distribution.
Claim 3
Dependent Claim
18 words
A device according to claim 1, wherein said particles have particle size of not more than 3 mm.
Claim 4
Dependent Claim
22 words
A device according to claim 2, wherein said particles have particle size of not less than 50μ but not more than 200μ.
Claim 5
Dependent Claim
20 words
A device according to claim 1, wherein the inorganic binder is an insulating binder having, as a main component, alumina.
Claim 6
Dependent Claim
13 words
A device according to claim 1, wherein said inorganic binder is heat-resistive glass.
Claim 7
Dependent Claim
66 words
A heating device according to claim 1, wherein said heat generating element is a heat generating layer of a first roller and said device further includes a second roller for transporting a supporting member through a nip formed between said first and second rollers for fixing a toner image on the supporting member, and means for rotating at least one of said first and second rollers.
Claim 8
Dependent Claim
35 words
A device according to claim 6, wherein said second roller is provided with a heat generating layer including ceramic particles made from pulverized ceramic having PTC characteristics and a binder dispersing the ceramic particles therein.
Claim 9
Dependent Claim
73 words
A heating device according to claim 1, wherein said heat generating element is a heat generating layer of a first roller and wherein said device further includes: second and third rollers for transporting a supporting member through a nip formed therebetween, said second roller being heated by said first roller to fix a toner image on the supporting member; and means for rotating at least one of said first, second and third rollers.
Claim 10
Dependent Claim
41 words
A device according to claim 8, wherein at least one of said second and third rollers is provided with a heat generating layer including ceramic particles made from pulverized ceramic having PTC characteristics and a binder dispersing the ceramic particles therein.
Claim 11
Dependent Claim
26 words
A device according to claim 6 or 8, wherein said voltage applying means has electrodes for voltage application at the longitudinal ends of said first roller.
Claim 12
Dependent Claim
29 words
A device according to claim 6 or 8, wherein said voltage applying means includes electrodes at exterior and interior surfaces of said heat generating layer of said first roller.
Claim 13
Dependent Claim
21 words
A device according to claim 6 or 8, wherein said ceramic particles have particle size of not more than 3 mm.
Claim 14
Dependent Claim
22 words
A device according to claim 12, wherein said particles have particle size of not less than 50μ, but not more than 200μ.
Claim 15
Dependent Claim
22 words
A device according to claim 6 or 8, wherein the inorganic binder is an insulating binder having, as a main component, alumina.
Claim 16
Dependent Claim
15 words
A device according to claim 6 or 8, wherein said inorganic binder is heat-resistive glass.
Claim 17
Dependent Claim
17 words
A device according to claim 6 or 8, wherein said first roller has a top releasing layer.
Claim 18
Dependent Claim
25 words
A device according to claim 6 or 8, wherein said binder of the heat generating layer of the first roller is of a releasing nature.
Claim 19
Dependent Claim
23 words
A device according to claim 17, wherein the thermal conductivity of the binder is substantially the same as that of the ceramic particles.
Claim 20
Dependent Claim
21 words
A device according to claim 17, wherein the thermal conductivity of the binder is greater than that of the ceramic particles.
Claim 21
Dependent Claim
34 words
A heating device according to claim 1, wherein said heat generating element is a heat generating layer of a plate-like heating member for generating heat to fix a toner image on a supporting member.
Claim 22
Dependent Claim
26 words
A device according to claim 20, wherein said voltage applying means has electrodes for applying voltage or current across the thickness of the heat generating layer.
Claim 23
Dependent Claim
29 words
A device according to claim 20, wherein said voltage applying means has electrodes for applying voltage or current in a direction transversing the thickness of the heat generating layer.
Claim 24
Dependent Claim
18 words
A device according to claim 20, wherein said particles have particle size of not more than 3 mm.
Claim 25
Dependent Claim
22 words
A device according to claim 23, wherein said particles have particle size of not less than 50μ but not more than 200μ.
Claim 26
Dependent Claim
20 words
A device according to claim 20, wherein the inorganic binder is an insulating binder having, as a main component, alumina.
Claim 27
Dependent Claim
13 words
A device according to claim 20, wherein said inorganic binder is heat-resistive glass.
Claim 28
Dependent Claim
25 words
A device according to claim 20, wherein said plate has a releasing layer on the side of said heat generating layer opposing the supporting member.
Claim 29
Dependent Claim
18 words
A device according to claim 20, wherein the binder of said heat generating layer has a releasing nature.
Claim 30
Independent Claim
27 words
A device according to claims 1, 6, 8 or 20, wherein the thermal conductivity of the binder is substantially the same as that of the ceramic particles.
Claim 31
Dependent Claim
25 words
A device according to claim 1, 6, 8 or 20, wherein the thermal conductivity of the binder is greater than that of the ceramic particles.
Claim 32
Dependent Claim
13 words
A device according to claim 1, wherein said heat generating element is roller-shaped.
Claim 33
Dependent Claim
13 words
A device according to claim 1, wherein said heat generating element is plate-shaped.
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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) | 1988-09-30 | 1989-04-01 | 1989-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-30 | 1993-04-01 | 1993-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-30 | 1997-04-01 | 1997-10-01 | $7700.00 | Window Closed / Lapsed |