US3775628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Insulated coil for arrangement in a slot in the stator or rotor of an electric machine
Assignee: ABB Norden Holding AB
•
Filing: 1972-07-10
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Granted: 1973-11-27
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Expires: 1992-07-10
Abstract
Abstract A coil positioned in the slot of a stator or rotor of an electric machine is formed of a bundle of conductors arranged close together and insulated from each other and from the slot. The conductor insulation consists of corona resistant insulating material running longitudinally of the conductor and surrounding the parts of the conductors facing the main insulation which surrounds the bundle of conductors and also overlies at least those part of the faces of the conductors which face the adjacent conductors which parts are situated nearest the tape facing the main insulation. The tape is formed of a linear unbranched or branched polymer having such thermal stability that the dielectric strength of a film of the polymer 50 microns in thickness, after ageing in air at 155*C for 25,000 hours, is at least 50 percent of the dielectric strength before the ageing and of mica in the form of small flakes.
Inventors
- 👤 A Andersson
- 👤 A Bjorklund
- 👤 L Virsberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:34
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/32; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/251; Y10T428/29; Y10T428/2911
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
186 words
Coil to be arranged in the slot of a stator or rotor in an electric machine, comprising a bundle of several conductors arranged close together and provided with conductor insulation to insulate the conductors from each other and a main insulation surrounding the bundle to insulate the bundle from the machine slot, the conductors having sides facing each other and at least one side facing the main insulation, said conductor having conductor insulation comprising tape means of insulating material running in the longitudinal direction of the conductor, the tape means surrounding said one side facing the main insulation and at least those parts of the sides facing adjacent conductors which are situated nearest said one side, at least one layer of the tape means being positioned between adjacent conductors, the tape means comprising a linear unbranched or branched polymer having such thermal stability that the dielectric strength of a film of the polymer 50 microns in thickness, after ageing in air at 155*C for 25,000 hours, is at least 50 percent of the dielectric strength before the ageing and mica in the form of small flakes.
Claim 2
Dependent Claim
186 words
Coil to be arranged in the slot of a stator or rotor in an electric machine, comprising a bundle of several conductors arranged close together and provided with conductor insulation to insulate the conductors from each other and a main insulation surrounding the bundle to insulate the bundle from the machine slot, the conductors having sides facing each other and at least one side facing the main insulation, said conductor having conductor insulation comprising tape means of insulating material running in the longitudinal direction of the conductor, the tape means surrounding said one side facing the main insulation and at least those parts of the sides facing adjacent conductors which are situated nearest said one side, at least one layer of the tape means being positioned between adjacent conductors, the tape means comprising a linear unbranched or branched polymer having such thermal stability that the dielectric strength of a film of the polymer 50 microns in thickness, after ageing in air at 155*C for 25,000 hours, is at least 50 percent of the dielectric strength before the ageing and mica in the form of small flakes.
Claim 3
Dependent Claim
30 words
Coil according to claim 1, in which the tape means of insulating material is built up of a coherent film of the polymer with the mica flakes embedded as filler.
Claim 4
Dependent Claim
40 words
A coil according to claim 1, in which the tape means of insulating material is built up of a coherent film of the polymer with the mica flakes arranged as a layer on at least one side of the film.
Claim 5
Dependent Claim
28 words
Coil according to claim 1, in which the tape means of insulating material is built up of a mixture of mica flakes and short fibres of the polymer.
Claim 6
Dependent Claim
33 words
Coil according to claim 1, in which the tape means of insulating material is wider than the circumference of the conductor and is folded around the conductor with the edges overlapping each other.
Claim 7
Dependent Claim
14 words
Coil according to claim 5, in which said tape means comprises a single tape.
Claim 8
Dependent Claim
100 words
Coil accordiNg to claim 4, in which the tape means comprises a tape of insulating material surrounding only one side of the conductor facing the main insulation and at least those parts of the sides of the conductor facing adjacent conductors which are situated nearest said one side, another tape of insulating material surrounding one side of the conductor positioned opposite to said one side facing the main insulation and at least those parts of the sides of the conductor facing adjacent conductors which are situated nearest to said side positioned opposite to said one side facing the main insulation.
Claim 9
Dependent Claim
79 words
Coil according to claim 6, in which said two tapes overlie parts only of the sides facing adjacent conductors and the gap between the edges of the two tapes on one side of a first conductor facing an adjacent conductor is displaced laterally in relation to the gap between the edges of the two tapes on the side of the adjacent conductor facing the first conductor so that at least one layer of tape is present between the conductors.
Claim 10
Dependent Claim
90 words
Coil according to claim 1, in which the tape means comprises a single tape surrounding one side of the conductor facing the main insulation, one side of the conductor positioned opposite to said one side facing the main insulation, one side of the conductor facing an adjacent conductor and at least those parts of another side of the conductor facing another adjacent conductor which are situated nearest said one side of the conductor facing the main insulation and said one side positioned opposite to said side facing the main insulation.
Claim 11
Dependent Claim
32 words
Coil according to claim 1, in which the main insulation comprises a wrapping of a tape or sheet shaped insulating material with mica as component in order to achieve good electric strength.
Claim 12
Dependent Claim
35 words
Coil according to claim 1, in which the polymer consists essentially of a substance selected from the group consisting of polyamide imides, polyamides, polyimides, and polymers based on polyhydantoin, polyethylene glycol terephthalate, polycarbonate and polysulphon.
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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) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |