US3906267A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brushless electric motors
Assignee: Sagem SA
•
Filing: 1974-05-16
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Granted: 1975-09-16
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Expires: 1994-05-16
Abstract
Abstract A D.C. brushless electric motor comprises a stator and a rotor. The rotor has two side cheeks arranged at the two sides of the stator in the axial direction, each having n teeth of like polarity (n being an integer greater than 1). The power winding comprises 2n clusters of radially directed electrical conductors and the axis of each cluster is offset electrically by 180* from that of the preceding cluster. The clusters are connected so that two successive clusters are traversed by currents flowing in the opposite directions. The power winding is embedded in an insulating annulus of moulded material. The stator additionally carries detection means (such as an additional winding) which are offset from the clusters electrically through 90*.
Inventors
- 👤 Claude Coupin
- 👤 Alain Deval
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:27
CPC Classifications
H; H02; H02K; H02K3/00; H02K21/00; H02K21/38
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
192 words
A D.C. brushless electric motor comprising a stator provided with a coiled power winding and a rotor comprising two side cheeks of magnetic material each having n teeth of like polarity, the side cheeks being arranged at the two sides of the stator in the axial direction and the magnetic flux provided by a member disposed radially inwardly the winding in the axial direction being closed parallel to the axis between the teeth of the side cheeks, wherein the power winding comprises 2n clusters of radially directed conductors, the axis of each cluster being offset electrically by 180* from that of the preceding cluster and the clusters being grouped so that two successive clusters are traversed by currents flowing in opposite directions, the said winding being embedded in an insulating annulus of moulded material which holds the clusters in position and has substantially parallel faces opposite the teeth of the side cheeks for the input and emergence of magnetic flux, which flux passes through non ferromagnetic material only between the said teeth, and that the stator carries detection means which are offset from the clusters of the power windings electrically through 90*.
Claim 2
Dependent Claim
192 words
A D.C. brushless electric motor comprising a stator provided with a coiled power winding and a rotor comprising two side cheeks of magnetic material each having n teeth of like polarity, the side cheeks being arranged at the two sides of the stator in the axial direction and the magnetic flux provided by a member disposed radially inwardly the winding in the axial direction being closed parallel to the axis between the teeth of the side cheeks, wherein the power winding comprises 2n clusters of radially directed conductors, the axis of each cluster being offset electrically by 180* from that of the preceding cluster and the clusters being grouped so that two successive clusters are traversed by currents flowing in opposite directions, the said winding being embedded in an insulating annulus of moulded material which holds the clusters in position and has substantially parallel faces opposite the teeth of the side cheeks for the input and emergence of magnetic flux, which flux passes through non ferromagnetic material only between the said teeth, and that the stator carries detection means which are offset from the clusters of the power windings electrically through 90*.
Claim 3
Dependent Claim
40 words
A motor according to claim 1, characterized in that each cluster of the power winding has an angular amplitude of the order of 90* electrically and that the angular amplitude of each tooth is more than that of a cluster.
Claim 4
Dependent Claim
39 words
A motor according to claim 1, wherein the clusters are constituted by a winding having 2n adjacent coils, two successive coils being wound in opposite senses and each cluster being made of adjacent radial conductors of two successive coils.
Claim 5
Dependent Claim
33 words
A motor in accordance with claim 1, wherein the clusters are constituted by a winding having n coils, each cluster being constituted by the radial conductors disposed on one side of the coils.
Claim 6
Dependent Claim
67 words
A motor in accordance with claim 1, wherein the detection means comprise a winding similar to the power winding and embedded in the same insulating annulus, the clusters of the detection winding being electrically offset by 90* from the clusters of the power winding and the peripheral connecting conductors between the clusters being axially offset in opposite senses as beTween the power winding and the detection winding.
Claim 7
Dependent Claim
49 words
A motor in accordance with claim 1, wherein the detection means comprise a second winding embedded in an annulus of moulded insulating material which is fast with the stator of the machine and so disposed as to have the migrant flux from one of the side cheeks passing therethrough.
Claim 8
Dependent Claim
51 words
A motor in accordance with claim 1, wherein the detection means comprise a winding with 8n semiclusters, constituted by coils placed between the clusters of the power winding, and connected and grouped so as to provide 2n only active clusters offset electrically by 90* from the clusters of the driving winding.
Claim 9
Dependent Claim
25 words
A motor in accordance with claim 1, wherein the member which produces the magnetic flux is an annular magnet rigidly connected to the side cheeks.
Claim 10
Dependent Claim
24 words
A motor in accordance with claim 1, wherein the teeth of the side cheeks are bent inwardly of the machine in the axial sense.
Claim 11
Dependent Claim
36 words
A motor is accordance with claim 1, wherein the side cheeks are flat and the member which produces the magnetic flux is a magnet of high magnetic energy material which is fast with the side cheeks.
References Cited (Backward Citations)
US286247A
Cited
US3261998A
Cited
US3348086A
Cited
US3343014A
Cited
US3467844A
Cited
US3845339A
Cited
US3840761A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |