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Patent US4399190A successfully refreshed from Google Patents.
US4399190A
Expired / Lapsed
US
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Thin insulating mica sheet and insulated coil
Assignee: Mitsubishi Electric Corp
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Filing: 1982-01-28
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Granted: 1983-08-16
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Expires: 2002-01-28
Abstract
Abstract A thin insulating sheet comprises an associated mica sheet containing 1 to 9 wt. % of a polymer fibril which is melt-bonded to a polymer film or a porous polymer sheet and impregnated with a resin in a prepreg form.
Inventors
- 👤 Tadashi Iwabuchi
- 👤 Osamu Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:04
CPC Classifications
B; B32; B32B; B32B19/00; B32B19/04; B32B19/045; B32B27/00; B32B27/28; B32B27/281; B32B27/34; B32B27/36; H; H01; H01B; H01B3/00; H01B3/02; H01B3/04; H01F; H01F27/00; H01F27/28; H01F27/32; H01F27/327; B32B2260/00; B32B2260/04; B32B2260/046; B32B2262/00; B32B2262/02; B32B2262/0261; B32B2262/0269; B32B2305/00; B32B2305/07; B32B2305/076; B32B2307/00; B32B2307/20; B32B2307/206; B32B2315/00; B32B2315/10; B32B2367/00; B32B2377/00; B32B2379/00; B32B2379/08; B32B2457/00; B32B2457/04; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/29; Y10T428/2911; Y10T428/31504; Y10T428/31511; Y10T428/31515; Y10T428/31518; Y10T428/31721; Y10T428/31725; Y10T428/31728; Y10T428/31786
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
73 words
A thin insulating sheet which comprises an associated mica sheet containing 1 to 9 wt.% of a polymer fibril which is melt-bonded to a polymer film without using a binder, the melt-bonded composite having a thickness of 35-65 μm, and impregnated with a resin in a prepreg form, wherein said polymer film is selected from the group consisting of a polyimide film, a polyparabanic acid film, a polyamide film and a polyester film.
Claim 2
Dependent Claim
73 words
A thin insulating sheet which comprises an associated mica sheet containing 1 to 9 wt.% of a polymer fibril which is melt-bonded to a polymer film without using a binder, the melt-bonded composite having a thickness of 35-65 μm, and impregnated with a resin in a prepreg form, wherein said polymer film is selected from the group consisting of a polyimide film, a polyparabanic acid film, a polyamide film and a polyester film.
Claim 3
Dependent Claim
20 words
The thin insulating sheet according to claim 1 wherein said polymer fibril is a pulp made of an aromatic polyamide.
Claim 4
Dependent Claim
49 words
The thin insulating sheet according to claim 2, wherein the aromatic polyamide has repeating units represented by the formula (1) or (2): --NH--Ar.sub.1 --NH--CO--Ar.sub.2 --CO-- (1) --NH--Ar.sub.3 --CO-- (2) wherein Ar 1 , Ar 2 and Ar 3 are the same or different and represent a di-valent aromatic group.
Claim 5
Dependent Claim
24 words
The thin insulating sheet according to claim 3, wherein said aromatic polyamide is selected from the group consisting of poly(m-phenyleneisophthalamide), poly(m-phenyleneterephthalamide), poly(p-phenyleneisophthalamide) and poly(p-phenyleneterephthalamide).
Claim 6
Dependent Claim
36 words
The thin insulating sheet according to claim 1 wherein said resin for impregnation is a thermosettable resin selected from the group consisting of a polyimide resin, a triazine resin, a silicone resin and an epoxy resin.
Claim 7
Dependent Claim
23 words
The thin insulating sheet according to claim 5, wherein said resin for impregnation is present in an amount of 30 to 50 wt.%.
Claim 8
Dependent Claim
23 words
The thin insulating sheet according to claim 6 wherein said resin for impregnation is present in an amount of 30 to 40 wt.%.
Claim 9
Dependent Claim
54 words
An insulated coil which comprises a thin insulating sheet obtained by melt-bonding an associated mica sheet containing 1 to 9 wt.% of a polymer fibril to a polymer film, without using a binder, and impregnating with a resin in a prepreg form which is used for a bare conductor insulation or a turn insulation.
Claim 10
Dependent Claim
54 words
An insulated coil which comprises a thin insulating sheet obtained by melt-bonding an associated mica sheet containing 1 to 9 wt.% of a polymer fibril to a polymer film, without using a binder, and impregnating with a resin in a prepreg form which is used for a bare conductor insulation or a turn insulation.
References Cited (Backward Citations)
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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) | 1986-08-15 | 1987-02-14 | 1987-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-15 | 1991-02-14 | 1991-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-15 | 1995-02-14 | 1995-08-16 | $7700.00 | Window Closed / Lapsed |