US5881349A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image induction heating apparatus
Assignee: Canon Inc
•
Filing: 1997-07-11
•
Granted: 1999-03-09
•
Expires: 2017-07-11
Abstract
Abstract An image heating apparatus is provided with: a moving member having an electrically conductive layer and arranged to move together with a recording medium, an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by the exciting coil generates eddy currents in the moving member and the eddy currents make the moving member generate heat, wherein the heat of the moving member heats an image on the recording medium, a magnetic member for guiding the magnetic flux generated by the exciting coil, wherein the moving member and the magnetic member form a substantially closed magnetic circuit, wherein an angle θ rad! formed between a principal line of magnetic force directed from the magnetic member to the moving member and a principal line of magnetic force directed from the moving member to the magnetic member is determined to be 0<θ<π.
Inventors
- 👤 Hideo Nanataki
- 👤 Hiroki Kisu
- 👤 Atsuyoshi Abe
- 👤 Tetsuya Sano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:32
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2053; H; H05; H05B; H05B6/00; H05B6/02; H05B6/10; H05B6/14; H05B6/145; G03G2215/00; G03G2215/20; G03G2215/2003
Claims Analysis
Total Claims: 62
Claim 1
Independent Claim
149 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member to make said rotational member generate heat, and an image on a recording medium being heated by the heat of said rotational member; a magnetic member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member is provided inside of said rotational member to form a substantially closed magnetic circuit, wherein an angle θ (rad) formed between a principle line of magnetic force directed from said magnetic member to said rotational member and a principle line of magnetic force directed from said rotational member to said magnetic member is determined to be 0<θ<π, and wherein said magnetic member is provided in a half region of said rotational member.
Claim 2
Dependent Claim
149 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member to make said rotational member generate heat, and an image on a recording medium being heated by the heat of said rotational member; a magnetic member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member is provided inside of said rotational member to form a substantially closed magnetic circuit, wherein an angle θ (rad) formed between a principle line of magnetic force directed from said magnetic member to said rotational member and a principle line of magnetic force directed from said rotational member to said magnetic member is determined to be 0<θ<π, and wherein said magnetic member is provided in a half region of said rotational member.
Claim 3
Dependent Claim
38 words
An image heating apparatus according to claim 1, further comprising a half cylindrical guide member provided inside of said rotational member for guiding movement of said rotational member, wherein said magnetic member is received in said guide member.
Claim 4
Dependent Claim
18 words
An image heating apparatus according to claim 2, wherein said exciting coil is received in said guide member.
Claim 5
Dependent Claim
34 words
An image heating apparatus according to claim 1, wherein said magnetic member has a first magnetic portion and a second magnetic portion through which each of said principle lines of magnetic force goes respectively.
Claim 6
Dependent Claim
30 words
An image heating apparatus according to claim 4, wherein an end portion of each of said first magnetic portion and said second magnetic portion is adjacent to said rotational member.
Claim 7
Dependent Claim
33 words
An image heating apparatus according to claim 4, wherein said second magnetic portion is provided upstream and downstream of said first magnetic portion with respect to a moving direction of said rotational member.
Claim 8
Dependent Claim
19 words
An image heating apparatus according to claim 6, wherein said exciting coil is wound around said first magnetic portion.
Claim 9
Dependent Claim
35 words
An image heating apparatus according to claim 4, further comprising a back-up member for forming a nip together with said rotational member, wherein an end of said first magnetic portion is opposed to said nip.
Claim 10
Dependent Claim
15 words
An image heating apparatus according to claim 1, wherein θ satisfies the relation π/6<θ<5 π/6.
Claim 11
Dependent Claim
12 words
An image heating apparatus according to claim 1, wherein θ is π/2.
Claim 12
Dependent Claim
40 words
An image heating apparatus according to claim 1, wherein said magnetic member is elongated in a direction perpendicular to a moving direction of said rotational member and said exciting coil is wound over a longitudinal direction of said magnetic member.
Claim 13
Dependent Claim
16 words
An image heating apparatus according to claim 1, wherein said rotational member is an endless film.
Claim 14
Dependent Claim
49 words
An image heating apparatus according to claim 1, further comprising a back-up member to form a nip together with said rotational member, wherein a recording medium which bears an unfixed toner image is nipped and conveyed at said nip to fix the unfixed toner image on the recording medium.
Claim 15
Dependent Claim
45 words
An image heating apparatus according to claim 1, wherein said principle line of magnetic force directed from said magnetic member to said rotational member of said principle line of magnetic force directed from said rotational member to said magnetic member occur at the same time.
Claim 16
Dependent Claim
203 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member and the eddy currents make said rotational member generate heat; a back-up member for forming a nip together with said rotational member, wherein a recording medium which bears an image is nipped and conveyed at said nip, the image on the recording medium being heated by the heat of said rotational member; and a magnetic member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member is provided inside of said rotational member, said rotational member and said magnetic member form a substantially closed magnetic circuit, an angle θ (rad) formed between a principle line of magnetic force directed from said magnetic member to said rotational member and a principle line of magnetic force directed from said rotational member to said magnetic member is determined to be 0<θ<π, and a central portion of a heat region of said rotational member generated by said closed magnetic circuit is located upstream of said nip with respect to a moving direction of said rotational member.
Claim 17
Dependent Claim
203 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member and the eddy currents make said rotational member generate heat; a back-up member for forming a nip together with said rotational member, wherein a recording medium which bears an image is nipped and conveyed at said nip, the image on the recording medium being heated by the heat of said rotational member; and a magnetic member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member is provided inside of said rotational member, said rotational member and said magnetic member form a substantially closed magnetic circuit, an angle θ (rad) formed between a principle line of magnetic force directed from said magnetic member to said rotational member and a principle line of magnetic force directed from said rotational member to said magnetic member is determined to be 0<θ<π, and a central portion of a heat region of said rotational member generated by said closed magnetic circuit is located upstream of said nip with respect to a moving direction of said rotational member.
Claim 18
Dependent Claim
52 words
An image heating apparatus according to claim 15, wherein said magnetic member has a first magnetic portion and a second magnetic portion each of which said principle line of magnetic force goes through respectively, wherein said first magnetic portion, said second magnetic portion and said rotational member form a closed magnetic circuit.
Claim 19
Dependent Claim
18 words
An image heating apparatus according to claim 16, wherein said first magnetic portion is opposed to said nip.
Claim 20
Dependent Claim
32 words
An image heating apparatus according to claim 16, wherein said second magnetic portion is provided upstream and downstream of said first magnetic portion with respect to moving direction of said rotational member.
Claim 21
Dependent Claim
19 words
An image heating apparatus according to claim 18, wherein said exciting coil is wound around said first magnetic portion.
Claim 22
Dependent Claim
13 words
An image heating apparatus according to claim 15, wherein θ is preferably π/6<θ<5π/6.
Claim 23
Dependent Claim
12 words
An image heating apparatus according to claim 15, wherein θ is π/2.
Claim 24
Dependent Claim
22 words
An image heating apparatus according to claim 15, wherein said magnetic member is provided in the half region of said rotational member.
Claim 25
Dependent Claim
38 words
An image heating apparatus according to claim 22, further comprising a half cylindrical guide member provided inside of said rotational member for guiding movement of said rotational member, wherein said magnetic member is received in said guide member.
Claim 26
Dependent Claim
18 words
An image heating apparatus according to claim 23, wherein said exciting coil is received in said guide member.
Claim 27
Dependent Claim
40 words
An image heating apparatus according to claim 15, wherein said magnetic member is elongated in a direction perpendicular to a moving direction of said rotational member and said exciting coil is wound over a longitudinal direction of said magnetic member.
Claim 28
Dependent Claim
16 words
An image heating apparatus according to claim 15, wherein said rotational member is an endless film.
Claim 29
Dependent Claim
35 words
An image heating apparatus according to claim 15, wherein a recording medium which bears an unfixed toner image is nipped and conveyed at said nip to fix the unfixed toner image on the recording medium.
Claim 30
Dependent Claim
45 words
An image heating apparatus according to claim 15, wherein said principle line of magnetic force directed from said magnetic member to said rotational member and said principle line of magnetic force directed from said rotational member to said magnetic member occur at the same time.
Claim 31
Dependent Claim
129 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member and the eddy currents make said rotational member generate heat, and an image on a recording medium being heated by the heat of said rotational member; and a magnetic member provided inside of said rotational member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member has a first magnetic portion and a second magnetic portion which is provided in a direction substantially perpendicular to said first magnetic portion, said first magnetic portion and said second magnetic portion are provided in the half region of said rotational member.
Claim 32
Dependent Claim
129 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member and the eddy currents make said rotational member generate heat, and an image on a recording medium being heated by the heat of said rotational member; and a magnetic member provided inside of said rotational member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member has a first magnetic portion and a second magnetic portion which is provided in a direction substantially perpendicular to said first magnetic portion, said first magnetic portion and said second magnetic portion are provided in the half region of said rotational member.
Claim 33
Dependent Claim
38 words
An image heating apparatus according to claim 29, further comprising a half cylindrical guide member provided inside of said rotational member for guiding movement of said rotational member, wherein said magnetic member is received in said guide member.
Claim 34
Dependent Claim
18 words
An image heating apparatus according to claim 30, wherein said exciting coil is received in said guide member.
Claim 35
Dependent Claim
48 words
An image heating apparatus according to claim 29, further comprising a back-up member for forming a nip together with said rotational member, wherein said first magnetic portion and said second magnetic portion are provided in the half region on the side of said nip of said rotational member.
Claim 36
Dependent Claim
18 words
An image heating apparatus according to claim 32, wherein said first magnetic portion is opposed to said nip.
Claim 37
Dependent Claim
33 words
An image heating apparatus according to claim 33, wherein said second magnetic portion is positioned at the first end of the first magnetic portion opposite to a second end facing to said nip.
Claim 38
Dependent Claim
33 words
An image heating apparatus according to claim 29, wherein said second magnetic portion is provided upstream and downstream of said first magnetic portion with respect to a moving direction of said rotational member.
Claim 39
Dependent Claim
19 words
An image heating apparatus according to claim 35, wherein said exciting coil is wound around said first magnetic portion.
Claim 40
Dependent Claim
26 words
An image heating apparatus according to claim 29, wherein ends of said first magnetic portion and said second magnetic portion are adjacent to said rotational member.
Claim 41
Dependent Claim
27 words
An image heating apparatus according to claim 29, wherein said rotational member, said first magnetic portion and said second magnetic portion form a substantially closed magnetic circuit.
Claim 42
Dependent Claim
56 words
An image heating apparatus according to claim 38, further comprising a back-up member for forming a nip together with said rotational member, wherein a central portion of a heat region of said rotational member generated by said closed magnetic circuit is located upstream of said nip with respect to a moving direction of said rotational member.
Claim 43
Dependent Claim
33 words
An image heating apparatus according to claim 29, wherein said magnetic member is of a T-shaped form when seen with respect to a direction perpendicular to a moving direction of said rotational member.
Claim 44
Dependent Claim
40 words
An image heating apparatus according to claim 29, wherein said magnetic member is elongated in a direction perpendicular to a moving direction of said rotational member and said exciting coil is wound over a longitudinal direction of said magnetic member.
Claim 45
Dependent Claim
16 words
An image heating apparatus according to claim 29, wherein said rotational member is an endless film.
Claim 46
Dependent Claim
49 words
An image heating apparatus according to claim 29, further comprising a back-up member for forming a nip together with said rotational member, wherein a recording medium which bears an unfixed toner image is nipped and conveyed at said nip to fix the unfixed toner image on the recording medium.
Claim 47
Dependent Claim
130 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member and the eddy currents make said rotational member generate heat, and an image on a recording medium is heated by the heat of said rotational member; and a magnetic member provided inside of said rotational member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member has a first magnetic portion and a second magnetic portion which is provided in a direction substantially perpendicular to said first magnetic portion, and said first magnetic portion and said second magnetic portion are rectangular parallelepiped, and both are independent of each other.
Claim 48
Dependent Claim
130 words
An image heating apparatus comprising: a rotational member having an electrically conductive layer; an exciting coil for generating a magnetic flux, wherein the magnetic flux generated by said exciting coil generates eddy currents in said rotational member and the eddy currents make said rotational member generate heat, and an image on a recording medium is heated by the heat of said rotational member; and a magnetic member provided inside of said rotational member for guiding the magnetic flux generated by said exciting coil, wherein said magnetic member has a first magnetic portion and a second magnetic portion which is provided in a direction substantially perpendicular to said first magnetic portion, and said first magnetic portion and said second magnetic portion are rectangular parallelepiped, and both are independent of each other.
Claim 49
Dependent Claim
35 words
An image heating apparatus according to claim 44, further comprising a back-up member for forming a nip together with said rotational member, wherein the end of said first magnetic portion is opposed to said nip.
Claim 50
Dependent Claim
33 words
An image heating apparatus according to claim 45, wherein said second magnetic portion is positioned at a first end of said first magnetic portion opposite to the second end facing to said nip.
Claim 51
Dependent Claim
33 words
An image heating apparatus according to claim 44, wherein said second magnetic portion is provided upstream and downstream of said first magnetic portion with respect to a moving direction of said rotational member.
Claim 52
Dependent Claim
19 words
An image heating apparatus according to claim 47, wherein said exciting coil is wound around said first magnetic portion.
Claim 53
Dependent Claim
27 words
An image heating apparatus according to claim 44, wherein end portions of said first magnetic portion and said second magnetic portion are adjacent to said rotational member.
Claim 54
Dependent Claim
27 words
An image heating apparatus according to claim 44, wherein said rotational member, said first magnetic portion and said second magnetic portion substantially form a closed magnetic circuit.
Claim 55
Dependent Claim
56 words
An image heating apparatus according to claim 50, further comprising a back-up member for forming a nip together with said rotational member, wherein a central portion of a heat region of said rotational member generated by said closed magnetic circuit is located upstream of said nip with respect to a moving direction of said rotational member.
Claim 56
Dependent Claim
33 words
An image heating apparatus according to claim 44, wherein said magnetic member is of a T-shaped form when seen with respect to a direction perpendicular to a moving direction of said rotational member.
Claim 57
Dependent Claim
28 words
An image heating apparatus according to claim 44, wherein said first magnetic portion and said second magnetic portion are provided in the half region of said rotational member.
Claim 58
Dependent Claim
38 words
An image heating apparatus according to claim 53, further comprising a half cylindrical guide member provided inside of said rotational member for guiding movement of said rotational member, wherein said magnetic member is received in said guide member.
Claim 59
Dependent Claim
47 words
An image heating apparatus according to claim 53, further comprising a back-up member for forming a nip together with said rotational member, said first magnetic portion and said second magnetic portion are provided in the half region on the side of said nip of said rotational member.
Claim 60
Dependent Claim
40 words
An image heating apparatus according to claim 44, wherein said magnetic member is elongated in a direction perpendicular to a moving direction of said rotational member and said exciting coil is wound over a longitudinal direction of said magnetic member.
Claim 61
Dependent Claim
16 words
An image heating apparatus according to claim 44, wherein said rotational member is an endless film.
Claim 62
Dependent Claim
49 words
An image heating apparatus according to claim 44, further comprising a back-up member for forming a nip together with said rotational member, wherein a recording medium which bears an unfixed toner image is nipped and conveyed at said nip to fix the unfixed toner image on the recording medium.
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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) | 2002-03-08 | 2002-09-07 | 2003-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-08 | 2006-09-07 | 2007-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-08 | 2010-09-07 | 2011-03-09 | $7700.00 | Window Closed / Lapsed |