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Dynamo electric machines

Assignee: QED Intellectual Property Ltd
•
Filing: 1971-09-27
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Granted: 1975-03-04
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Expires: 1991-09-27
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Abstract

Abstract A dynamo electric machine is described in which windings arranged for carrying alternating current are associated with pole pieces which are constructed from a magnetically soft ferrite material. The pole pieces are, in one example, formed as part of a stator arrangement, and a co-operating rotor arrangement includes a permanently magnetised structure which is constructed from a magnetically hard ferrite material. Such machines are especially suitable for use as alternators or motors.

Inventors

  • 👤 Michael Charles Puttock
  • 👤 Bryan Crosby Linfoot

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 07:30
CPC Classifications
H; H02; H02K; H02K21/00; H02K21/12; H02K21/24

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 106 words
A dynamo electric machine comprising a rotor member including an annulus of magnetically hard ferrite material with a plurality of magnetic domains arranged in a ring on one face thereof, adjacent domains being magnetised in different senses; and a stator member spAced from said rotor member and formed of magnetically soft material, said stator including a plurality of substantially cylindrical magnetically soft ferrite poles protruding therefrom arranged in a circle concentric with said annulus and having substantially circular faces directed towards said domains for establishing magnetic flux linkage therewith, each of said poles being encompassed by a plurality of closed loop windings of electrically conductive material.
Claim 2
Dependent Claim 106 words
A dynamo electric machine comprising a rotor member including an annulus of magnetically hard ferrite material with a plurality of magnetic domains arranged in a ring on one face thereof, adjacent domains being magnetised in different senses; and a stator member spAced from said rotor member and formed of magnetically soft material, said stator including a plurality of substantially cylindrical magnetically soft ferrite poles protruding therefrom arranged in a circle concentric with said annulus and having substantially circular faces directed towards said domains for establishing magnetic flux linkage therewith, each of said poles being encompassed by a plurality of closed loop windings of electrically conductive material.
Claim 3
Dependent Claim 12 words
A dynamo electric machine according to claim 1 arranged as an alternator.
Claim 4
Dependent Claim 12 words
A dynamo electric machine according to claim 1 arranged as a motor.
Claim 5
Dependent Claim 27 words
A dynamo electric machine according to claim 1 including eight pole pieces arranged in a ring on said stator, and eight magnetic domains formed on said rotor.
Claim 6
Dependent Claim 45 words
A dynamo electric machine according to claim 1 wherein said rotor and stator member respectively comprise a circular disc of magnetically hard ferrite and a circular disc of magnetically soft ferrite with the common axis of symmetry thereof forming the rotation axis of said rotor.
Claim 7
Dependent Claim 25 words
A dynamo electric machine according to claim 1 wherein said poles and said domains have substantially equal face areas for establishing magnetic flux linkage therebetween.

References Cited (Backward Citations)

US3230406A Cited
US3247407A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-03-03 1978-09-02 1979-03-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-03-03 1982-09-02 1983-03-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-03-03 1986-09-02 1987-03-04 $7700.00 Window Closed / Lapsed

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