US3789337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Insulation structure for electrical apparatus
Assignee: ABB Inc USA
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Filing: 1971-12-17
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Granted: 1974-01-29
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Expires: 1991-12-17
Abstract
Abstract Insulation structure having filler members which keep the overall insulation structure tight when heated. The filler members are located within the insulation structure at various places and in sufficient quantities, with the shortest dimension of the filler member oriented in the direction in which expansion is desired. As the insulation structure is heated, the shortest dimension of the filler member increases to tighten the insulation structure. The filler member is constructed from a material which tends to reduce its surface area when heated without changing its volume.
Inventors
- 👤 H Sheppard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:37
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/28; H01F27/30; H01F27/303
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
60 words
Electrical apparatus comprising electrical conductors separated by an insulation structure, said insulation structure including an insulating member and a plurality of spaced filler members which expand when heated to compress said insulation structure, said insulating and filler members being constructed of different materials, and each said filler members being prestretched in a direction along at least one of its dimensions.
Claim 2
Dependent Claim
60 words
Electrical apparatus comprising electrical conductors separated by an insulation structure, said insulation structure including an insulating member and a plurality of spaced filler members which expand when heated to compress said insulation structure, said insulating and filler members being constructed of different materials, and each said filler members being prestretched in a direction along at least one of its dimensions.
Claim 3
Dependent Claim
53 words
The electrical apparatus of claim 1 wherein a first dimension of a filler member tends to increase in size when heated and at least one of the other two dimensions tends to decrease in size when heated, said first dimension being oriented in a direction in which compressive forces tighten the insulation structure.
Claim 4
Dependent Claim
31 words
The electrical apparatus of claim 1 wherein a filler member is constructed of a material which has a tendency to decrease its surface area, when heated, without substantially changing its volume.
Claim 5
Dependent Claim
41 words
The electrical apparatus of claim 1 wherein a filler member is constructed of a material selected from the group of materials consisting of polytetrafluorethylene, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polyethylene, polypropylene, isotatic polystyrene, polyphenylene oxide, polycarbonate, nylon, and silicone rubber.
Claim 6
Dependent Claim
14 words
The electrical apparatus of claim 1 wherein the insulating member includes a cellulosic material.
Claim 7
Dependent Claim
25 words
The electrical apparatus of claim 1 wherein the first dimension of a filler member is not greater than its other two dimensions before being heated.
Claim 8
Dependent Claim
51 words
The electrical apparatus of claim 6 wherein the electrical conductors are formed into a hollow winding and disposed around a leg of a magnetic core of a transformer to form a core-winding structure, and wherein the insulation structure physically separates the electrical conductors from each other and from the magnetic core.
Claim 9
Dependent Claim
23 words
The electrical apparatus of claim 7 wherein a filler member has its first dimension oriented in a radial direction of the winding structure.
Claim 10
Dependent Claim
20 words
The electrical apparatus of claim 8 wherein a filler member is disposed between the electrical conductors of the winding structure.
Claim 11
Dependent Claim
21 words
The electrical apparatus of claim 8 wherein a filler member is disposed between the winding structure and the magnetic core leg.
Claim 12
Dependent Claim
26 words
The electrical apparatus of claim 8 wherein the winding structure comprises concentric windings and a filler member is disposed between concentric windings of the winding structure.
Claim 13
Dependent Claim
23 words
The electrical apparatus of claim 7 wherein a filler member has its first dimension oriented in the axial direction of the winding structure.
Claim 14
Dependent Claim
31 words
The electrical apparatus of claim 12 wherein the winding structure comprises a plurality of stacked coil disk windings and a filler member is disposed between coil disks of the winding structure.
Claim 15
Dependent Claim
30 words
The electrical apparatus of claim 12 wherein a pressure ring is disposed adjacent said winding structure and a filler member is disposed between the winding structure and the pressure ring.
Claim 16
Dependent Claim
19 words
The electrical apparatus of claim 7 wherein a filler member is wrapped around the insulation of the electrical conductors.
Claim 17
Dependent Claim
106 words
Electrical inductive apparatus comprising a laminated magnetic core, an insulated winding structure disposed in inductive relationship with said magnetic core, an insulation structure, end frame means for holding the laminations of said magnetic core together, a prestretched filler member disposed between said end frame means and said magnetic core, said filler member having a first dimension which tends to increase in size when heated, said first dimension of said filler member being not greater than its other two dimensions before being heated, said first dimension being oriented in the direction which is perpendicular to the adjacent faces of said magnetic core and said end frame means.
Claim 18
Dependent Claim
106 words
Electrical inductive apparatus comprising a laminated magnetic core, an insulated winding structure disposed in inductive relationship with said magnetic core, an insulation structure, end frame means for holding the laminations of said magnetic core together, a prestretched filler member disposed between said end frame means and said magnetic core, said filler member having a first dimension which tends to increase in size when heated, said first dimension of said filler member being not greater than its other two dimensions before being heated, said first dimension being oriented in the direction which is perpendicular to the adjacent faces of said magnetic core and said end frame means.
Claim 19
Dependent Claim
32 words
The electrical inductive apparatus of claim 16 wherein the filler member is constructed of a material which has a tendency to decrease its surface area, when heated, without substantially changing its volume.
Claim 20
Dependent Claim
42 words
The electrical inductive apparatus of claim 16 wherein the filler member is constructed of a material selected from the group of materials consisting of polytetrafluorethylene, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polyethylene, polypropylene, isotatic polystyrene, polyphenylene oxide, polycarbonate, nylon, and silicone rubber.
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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) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |