Patent US6049691A successfully refreshed from Google Patents.
US6049691A
Expired / Lapsed
US
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Image heating apparatus
Assignee: Canon Inc
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Filing: 1997-06-02
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Granted: 2000-04-11
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Expires: 2017-06-02
Abstract
Abstract An image heating apparatus has a heat generating element with an electroconductive portion; a magnetic flux generating unit for generating a magnetic flux, wherein the magnetic flux generated by the magnetic flux generating unit produces eddy current in the heat generating element to heat the heat generating element; a back-up member cooperating with the heat generating element to form a nip therebetween, wherein the nip feeds a recording material carrying an image; a pressing member for applying pressure to the nip; a holding member of metal for holding a pressure by the pressing member; and a shield member provided between the magnetic flux generating unit and the holding member, for shielding magnetic.
Inventors
- 👤 Atsuyoshi Abe
- 👤 Tohru Saito
- 👤 Hideo Nanataki
- 👤 Tetsuya Sano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:07
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2064; G03G15/2053
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
120 words
An image heating apparatus comprising: a heat generating element having an electroconductive portion; magnetic flux generating means for generating a magnetic flux, wherein said heat generating element generates heat by eddy current generated therein by the magnetic flux generated by said magnetic flux generating means; a back-up member cooperating with said heat generating element to form a nip therebetween, wherein the recording material carrying an image is nipped and fed by said nip so that the image is heated; a pressing member for applying pressure to said nip; a metallic holding member for holding the pressure applied by said pressing member; and a shield member, provided between said magnetic flux generating means and said holding member, for shielding magnetic flux.
Claim 2
Dependent Claim
120 words
An image heating apparatus comprising: a heat generating element having an electroconductive portion; magnetic flux generating means for generating a magnetic flux, wherein said heat generating element generates heat by eddy current generated therein by the magnetic flux generated by said magnetic flux generating means; a back-up member cooperating with said heat generating element to form a nip therebetween, wherein the recording material carrying an image is nipped and fed by said nip so that the image is heated; a pressing member for applying pressure to said nip; a metallic holding member for holding the pressure applied by said pressing member; and a shield member, provided between said magnetic flux generating means and said holding member, for shielding magnetic flux.
Claim 3
Dependent Claim
15 words
An apparatus according to claim 1, wherein said shield member is a non-magnetic electroconductive member.
Claim 4
Dependent Claim
28 words
An apparatus according to claim 2, wherein said shield member is of Al, Cu, Ag, Au or an alloy comprising at least one of Al, Cu, Ag, Au.
Claim 5
Dependent Claim
20 words
An apparatus according to claim 2, wherein said shield member has a volume resistivity of 3×10 -8 ohm.m or lower.
Claim 6
Dependent Claim
30 words
An apparatus according to claim 1, wherein a width, measured in a movement direction of the recording material, of said shield member is larger than that of said holding member.
Claim 7
Dependent Claim
19 words
An apparatus according to claim 1, wherein said magnetic flux generating means includes an excitation coil and a core.
Claim 8
Dependent Claim
35 words
An apparatus according to claim 6, wherein said shield member has a width, measured in a direction perpendicular to a movement direction of the recording material, which is larger than that of said excitation coil.
Claim 9
Dependent Claim
32 words
An apparatus according to claim 6, wherein said core is in the form of a rectangular parallelopiped elongated from a neighborhood of said nip in the pressing direction of said pressing member.
Claim 10
Dependent Claim
38 words
An apparatus according to claim 1, wherein said holding member is elongated in a direction perpendicular to a movement direction of the recording material, and said pressing member applies pressure to longitudinal end portions of said holding member.
Claim 11
Dependent Claim
38 words
An apparatus according to claim 9, wherein said shield member is elongated along said holding member, and has a width, measured in the pressing direction, reducing from longitudinally central portion toward the end portions of the shield member.
Claim 12
Dependent Claim
51 words
An apparatus according to claim 9, further comprising an electrically insulative member elongated along a holding member between said magnetic flux generating means and said shield member, said insulative member having a width, measured in the pressing direction, reducing from longitudinally central portion toward the end portions of the shield member.
Claim 13
Dependent Claim
15 words
An apparatus according to claim 1, wherein said holding member is composed of magnetic material.
Claim 14
Dependent Claim
19 words
An apparatus according to claim 12, wherein said holding member is composed of one of stainless steel and iron.
Claim 15
Dependent Claim
72 words
An apparatus according to claim 1, further comprising an electrically insulative member provided between said magnetic flux generating means and said shield member, and a guiding member for guiding movement of said heat generating element while supporting said magnetic flux generating means, wherein said insulative member is provided on said guiding member, and said shield member is provided on said insulative member, and said holding member is provided on said shield member.
Claim 16
Dependent Claim
33 words
An apparatus according to claim 14, wherein said pressing member applies pressure to back-up member through said holding member, said shield member, said insulative member, said guiding member and said heat generating element.
Claim 17
Dependent Claim
19 words
An apparatus according to claim 1, wherein said heat generating element is in the form of an endless film.
Claim 18
Dependent Claim
23 words
An apparatus according to claim 16, wherein said magnetic flux generating means, said holding member and said shield member, are inside said film.
Claim 19
Dependent Claim
27 words
An apparatus according to claim 1, wherein said heat generating element is fixed, and a film is provided between said heat generating element and said back-up member.
Claim 20
Dependent Claim
24 words
An apparatus according to claim 1, wherein said back-up member is in the form of a driving roller for driving said heat generating element.
Claim 21
Dependent Claim
18 words
An apparatus according to claim 1, wherein said shield member has a thickness of 0.5 mm or larger.
Claim 22
Dependent Claim
24 words
An apparatus according to claim 1, wherein a distance between said shield member and said magnetic flux generating means is 1 mm or larger.
Claim 23
Dependent Claim
47 words
An apparatus according to claim 21, wherein an electrically insulative member is provided between said shield member and said magnetic flux generating means, and a distance between said shield member and said magnetic flux generating means is substantially the same as a thickness of said insulative member.
Claim 24
Dependent Claim
180 words
An image heating apparatus comprising: a heat generating element having an electroconductive portion; magnetic flux generating means for generating a magnetic flux, wherein said heat generating element generates heat by eddy current generated therein by the magnetic flux generated by said magnetic flux generating means; a back-up member cooperating with said heat generating element to form a nip therebetween; wherein a recording material carrying an image is nipped and fed by said nip so that the image is heated; a pressing member for applying pressure to said nip; a holding member for holding the pressure applied by said pressing member, wherein said holding member is elongated in a direction perpendicular to the movement direction of the recording material, and said pressing member is provided at each longitudinal end of said holding member; and an intermediate member provided between said holding member and said nip and outside a portion where said magnetic flux generating means is closely opposed to said heat generating element, wherein said intermediate member has a crown configuration with respect to the longitudinal direction of said holding member.
Claim 25
Dependent Claim
180 words
An image heating apparatus comprising: a heat generating element having an electroconductive portion; magnetic flux generating means for generating a magnetic flux, wherein said heat generating element generates heat by eddy current generated therein by the magnetic flux generated by said magnetic flux generating means; a back-up member cooperating with said heat generating element to form a nip therebetween; wherein a recording material carrying an image is nipped and fed by said nip so that the image is heated; a pressing member for applying pressure to said nip; a holding member for holding the pressure applied by said pressing member, wherein said holding member is elongated in a direction perpendicular to the movement direction of the recording material, and said pressing member is provided at each longitudinal end of said holding member; and an intermediate member provided between said holding member and said nip and outside a portion where said magnetic flux generating means is closely opposed to said heat generating element, wherein said intermediate member has a crown configuration with respect to the longitudinal direction of said holding member.
Claim 26
Dependent Claim
17 words
An apparatus according to claim 23, wherein said intermediate member is convexed toward said holding member side.
Claim 27
Dependent Claim
16 words
An apparatus according to claim 23, wherein said intermediate member is convex toward said nip side.
Claim 28
Dependent Claim
41 words
An apparatus according to claim 23, wherein said intermediate member has a width, measured in a pressing direction of said pressing member, which reduces from a central portion to an end, with respect to a longitudinal direction of said holding member.
Claim 29
Dependent Claim
26 words
An apparatus according to claim 23, wherein said intermediate member includes an electrically insulative member provided between said holding member and said magnetic flux generating means.
Claim 30
Dependent Claim
39 words
An apparatus according to claim 23, wherein said magnetic flux generating means has an excitation coil and a core elongated along said holding member, and said pressing member urges said core through said holding member and said intermediate member.
Claim 31
Dependent Claim
54 words
An apparatus according to claim 23, further comprising a guiding member for guiding movement of said heat generating element while supporting said magnetic flux generating means, and said pressing member urges said back-up member through said holding member, said intermediate member, said magnetic flux generating means, said guiding member and said heat generating element.
Claim 32
Dependent Claim
12 words
An apparatus according to claim 23, wherein said holding member is metallic.
Claim 33
Dependent Claim
13 words
An apparatus according to claim 23, wherein said pressing member is a spring.
Claim 34
Dependent Claim
19 words
An apparatus according to claim 23, wherein said heat generating element is in the form of an endless film.
Claim 35
Dependent Claim
23 words
An apparatus according to claim 32, wherein said holding member, said intermediate member and said magnetic flux generating means are inside said film.
Claim 36
Dependent Claim
27 words
An apparatus according to claim 23, wherein said heat generating element is fixed, and a film is provided between said heat generating element and said back-up member.
Claim 37
Dependent Claim
24 words
An apparatus according to claim 23, wherein said back-up member is in the form of a driving roller for driving said heat generating element.
Claim 38
Dependent Claim
13 words
An apparatus according to claim 23, wherein said intermediate member is of metal.
Claim 39
Dependent Claim
14 words
An apparatus according to claim 23, wherein said intermediate member blocks the magnetic flux.
Claim 40
Dependent Claim
20 words
An apparatus according to claim 23, wherein said magnetic flux generating means includes an excitation coil and a core member.
Claim 41
Dependent Claim
171 words
An image heating apparatus comprising: a heat generating element having an electroconductive portion; magnetic flux generating means for generating a magnetic flux, wherein said heat generating element generates heat by eddy current generated therein by the magnetic flux generated by said magnetic flux generating means; a back-up member cooperating with said heat generating element to form a nip therebetween, wherein a recording material carrying an image is nipped and fed by said nip so that the image is heated; a pressing member for applying pressure to said nip, said pressing member being disposed at each end of said nip in a direction perpendicular to a movement direction of the recording material; a holding member for holding the pressure applied by said pressing member; and an intermediate member provided between said holding member and said nip and outside a portion where said magnetic flux generating means is closely opposed to said heat generating element, wherein said intermediate member has a crown configuration with respect to the longitudinal direction of said holding member.
Claim 42
Dependent Claim
171 words
An image heating apparatus comprising: a heat generating element having an electroconductive portion; magnetic flux generating means for generating a magnetic flux, wherein said heat generating element generates heat by eddy current generated therein by the magnetic flux generated by said magnetic flux generating means; a back-up member cooperating with said heat generating element to form a nip therebetween, wherein a recording material carrying an image is nipped and fed by said nip so that the image is heated; a pressing member for applying pressure to said nip, said pressing member being disposed at each end of said nip in a direction perpendicular to a movement direction of the recording material; a holding member for holding the pressure applied by said pressing member; and an intermediate member provided between said holding member and said nip and outside a portion where said magnetic flux generating means is closely opposed to said heat generating element, wherein said intermediate member has a crown configuration with respect to the longitudinal direction of said holding member.
References Cited (Backward Citations)
US4570044A
Cited
US5177549A
Cited
US5153654A
Cited
US5196895A
Cited
US5303016A
Cited
US5438398A
Cited
US5568240A
Cited
US5526103A
Cited
US5666627A
Cited
JPH0816007A
Cited
JPH0830126A
Cited
JPH0844227A
Cited
JPH0926717A
Cited
US5713069A
Cited
US5870660A
Cited
US5970299A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-04-11 | 2003-10-11 | 2004-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-04-11 | 2007-10-11 | 2008-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-04-11 | 2011-10-11 | 2012-04-11 | $7700.00 | Window Closed / Lapsed |