US4780634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alternating-current electrical generators
Assignee: Dowty Fuel Systems Ltd
•
Filing: 1987-07-08
•
Granted: 1988-10-25
•
Expires: 2007-07-08
Abstract
Abstract An alternating electrical generator which is adapted to reduce/eliminate "Iron losses" and the associated problems of overheating of the windings comprises a rotor; a plurality of pole sections spaced around the circumference of a rotor core member at a constant pole section pitch; a toothed stator; two or more independent windings; and, a plurality of bridge members to separate adjacent windings. The bridge members have a length equal to an even number of pole section lengths, to ensure that any bridge member is exposed to equal amount of each magnetic polarity. Thereby, ensuring that the net effect under the bridge member is zero.
Inventors
- 👤 John M. Masterman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:36
CPC Classifications
H; H02; H02K; H02K21/00; H02K21/48
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
126 words
An alternating-current electrical generator having reduced iron loss characteristics, which comprises: a rotor including a plurality of circumferentially spaced pole sections, each pole section has a pole section length that is substantially identical to the length of the other pole sections spaced about the circumference of the rotor; a stator, which has a number of teeth; at least two independent windings, each independent winding being electrically independent of one another and being wound on the teeth of the stator; and a plurality of bridge members having a length equal to an even number of pole section lengths; wherein the pole sections are circumferentially spaced at a constant pitch, and each of said bridge members is positioned between said at least two independent windings adjacent one another.
Claim 2
Dependent Claim
126 words
An alternating-current electrical generator having reduced iron loss characteristics, which comprises: a rotor including a plurality of circumferentially spaced pole sections, each pole section has a pole section length that is substantially identical to the length of the other pole sections spaced about the circumference of the rotor; a stator, which has a number of teeth; at least two independent windings, each independent winding being electrically independent of one another and being wound on the teeth of the stator; and a plurality of bridge members having a length equal to an even number of pole section lengths; wherein the pole sections are circumferentially spaced at a constant pitch, and each of said bridge members is positioned between said at least two independent windings adjacent one another.
Claim 3
Dependent Claim
25 words
A generator as claimed in claim 1 wherein each of the bridge members is supported by at least one unwound tooth carried by the stator.
Claim 4
Dependent Claim
19 words
A generator as claimed in claim 2 wherein there are two unwound teeth supporting each of the bridge members.
Claim 5
Dependent Claim
20 words
A generator as claimed in claim 2 wherein there are the three unwound teeth suporting each of the bridge members.
Claim 6
Dependent Claim
16 words
A generator as claimed in claim 2 wherein the stator is formed from a laminated structure.
Claim 7
Dependent Claim
14 words
A generator as claimed in claim 1 wherein the pole sections are permanent magnets.
Claim 8
Dependent Claim
136 words
An alternating-current electrical generator, having reduced iron loss characteristics, which comprises: a rotor including a plurality of circumferentially spaced pole sections, each pole section has a pole section length that is substantially identical to the length of the other pole sections spaced about the circumference of the rotor; a stator having a number of teeth; at least two independent windings, each independent winding being electrically independent of one another and being wound on the teeth of the stator; and at least two bridge members having a length equal to an even number of pole section lengths; wherein each bridge member is positioned between adjacent independent windings so that the resulting fluxes induced in each bridge member are substantially equal but opposite one another thereby essentially eliminating the flux effects and reducing iron losses of the generator.
Claim 9
Dependent Claim
136 words
An alternating-current electrical generator, having reduced iron loss characteristics, which comprises: a rotor including a plurality of circumferentially spaced pole sections, each pole section has a pole section length that is substantially identical to the length of the other pole sections spaced about the circumference of the rotor; a stator having a number of teeth; at least two independent windings, each independent winding being electrically independent of one another and being wound on the teeth of the stator; and at least two bridge members having a length equal to an even number of pole section lengths; wherein each bridge member is positioned between adjacent independent windings so that the resulting fluxes induced in each bridge member are substantially equal but opposite one another thereby essentially eliminating the flux effects and reducing iron losses of the generator.
References Cited (Backward Citations)
US1401996A
Cited
US3207935A
Cited
DE1942855A1
Cited
US3858308A
Cited
US4144470A
Cited
US4163915A
Cited
US4554491A
Cited
US4700098A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-25 | 1992-04-25 | 1992-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-25 | 1996-04-25 | 1996-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-25 | 2000-04-25 | 2000-10-25 | $7700.00 | Window Closed / Lapsed |