US3692928A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical bushing having a capacitor chain formed by overlapping capacitor elements
Assignee: Westinghouse Electric Corp
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Filing: 1971-05-24
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Granted: 1972-09-19
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Expires: 1991-05-24
Abstract
Abstract An electrical bushing having electrical insulation disposed about an axially extending conductor, and a plurality of stress grading elements disposed in the insulation to grade radial and longitudinal stresses in the bushing. These stress grading elements includes at least two groups of substantially tubular elements, with the elements of each group being axially spaced and dimensioned such that the wall portions of each group are substantially aligned. The aligned space between two elements of one group is bridged by an element of an adjacent group.
Inventors
- 👤 Kevin F Friedrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:09
CPC Classifications
H; H01; H01B; H01B17/00; H01B17/26; H01B17/28
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
186 words
An electrical bushing adapted for mounting in the casing of electrical apparatus, comprising: an axially extending electrical conductor having first and second ends, solid insulating means disposed about said electrical conductor, stress grading means disposed in said solid insulating means, including at least first and second groups of substantially tubular stress grading elements disposed coaxially with said electrical conductor, said first group of stress grading elements being axially spaced from one another and dimensioned such that their wall portions are substantially in alignment, said second group of stress grading elements being axially spaced from one another and dimensioned such that their wall portions are substantially in alignment, with the resulting aligned group being radially spaced from the first aligned group of stress grading elements, said first and second groups of stress grading elements being axially offset from one another such that each of the stress grading elements of the second group overlaps the ends of two stress grading elements, said stress grading elements being disposed such that there is a maximum of two stress grading elements above ground potential at any location perpendicular to said conductor.
Claim 2
Dependent Claim
186 words
An electrical bushing adapted for mounting in the casing of electrical apparatus, comprising: an axially extending electrical conductor having first and second ends, solid insulating means disposed about said electrical conductor, stress grading means disposed in said solid insulating means, including at least first and second groups of substantially tubular stress grading elements disposed coaxially with said electrical conductor, said first group of stress grading elements being axially spaced from one another and dimensioned such that their wall portions are substantially in alignment, said second group of stress grading elements being axially spaced from one another and dimensioned such that their wall portions are substantially in alignment, with the resulting aligned group being radially spaced from the first aligned group of stress grading elements, said first and second groups of stress grading elements being axially offset from one another such that each of the stress grading elements of the second group overlaps the ends of two stress grading elements, said stress grading elements being disposed such that there is a maximum of two stress grading elements above ground potential at any location perpendicular to said conductor.
Claim 3
Dependent Claim
22 words
The electrical bushing of claim 1 wherein at least certain of the stress grading elements are in the form of a frustrum.
Claim 4
Dependent Claim
23 words
The electrical bushing of claim 1 wherein at least certain of the stress grading elements are in the form of a straight cylinder.
Claim 5
Dependent Claim
24 words
The electrical bushing of claim 1 wherein at least certain of the elements are formed of a semiconductive material having a voltage dependent resistivity.
Claim 6
Dependent Claim
19 words
The electrical bushing of claim 1 wherein the axial lengths of the stress grading elements are substantially the same.
Claim 7
Dependent Claim
21 words
The electrical bushing of claim 1 wherein the axial lengths of at least certain of the stress grading elements are different.
Claim 8
Dependent Claim
20 words
The electrical bushing of claim 1 wherein the axial spacing in each group of stress grading elements is the same.
Claim 9
Dependent Claim
24 words
The electrical bushing of claim 1 wherein the axial spacing between the stress grading elements in each group is changed in a predetermined pattern.
Claim 10
Dependent Claim
26 words
The electrical bushing of claim 1 wherein the radial spacing between the aligned groups is the same from one end of the bushing to the other.
Claim 11
Dependent Claim
28 words
The electrical bushing of claim 1 wherein the radial spacing between adjacent aligned groups changes in a predetermined relationship from one end of the busing to the other.
Claim 12
Dependent Claim
72 words
The electrical bushing of claim 1 including at least one additional group of stress grading elements, with the elements of the first and second groups, and the elements of the at least one additional group being axially located such that each space between adjacent stress grading elements of one group is bridged by a stress grading element from an adjacent group, without any overlapping of elements of the first and third groups.
Claim 13
Dependent Claim
140 words
An electrical bushing adapted for mounting iN the casing of electrical apparatus, comprising: an axially extending electrical conductor having first and second ends, insulating means disposed about said electrical conductor, stress grading means disposed in said insulating means, including a plurality of groups of substantially tubular stress grading elements disposed coaxially with said electrical conductor, the elements in each of said groups being axially spaced from one another and dimensioned such that their wall portions are substantially in alignment, each of said aligned groups being radially spaced from one another, the elements in the plurality of groups being axially offset from one another such that each space between adjacent stress grading elements of one group is bridged by a stress grading element from an adjacent group, with a maximum of two elements overlapping at any location perpendicular to said conductor.
Claim 14
Dependent Claim
140 words
An electrical bushing adapted for mounting iN the casing of electrical apparatus, comprising: an axially extending electrical conductor having first and second ends, insulating means disposed about said electrical conductor, stress grading means disposed in said insulating means, including a plurality of groups of substantially tubular stress grading elements disposed coaxially with said electrical conductor, the elements in each of said groups being axially spaced from one another and dimensioned such that their wall portions are substantially in alignment, each of said aligned groups being radially spaced from one another, the elements in the plurality of groups being axially offset from one another such that each space between adjacent stress grading elements of one group is bridged by a stress grading element from an adjacent group, with a maximum of two elements overlapping at any location perpendicular to said conductor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |