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US3567979A Expired / Lapsed US ⏱️ 0.0 years remaining

Permanent magnet motors having split pole structures

Assignee: Singer Co
•
Filing: 1969-08-27
•
Granted: 1971-03-02
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Expires: 1989-08-27
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Abstract

Abstract A permanent magnetic motor is disclosed in which each of the main poles is made up of two distinct parts. One part is a ceramic permanent magnet having very low permeability. The other part is made of soft steel of relatively high permeability. The armature reaction magnetomotive force (MMF) produces flux in the soft steel part related to the armature current and this flux is in a direction to add to the main flux supplied by the permanent magnet part and imparts a partial series motor characteristic to the motor without requiring a field winding. Performance of the motor is upgraded, especially when operating on rectified alternating current, due to an improved torque to current ratio for a given permanent magnet.

Inventors

  • 👤 Wolfgang Jaffe
  • 👤 Dwight W Aten

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 13:41
CPC Classifications
H; H02; H02K; H02K23/00; H02K23/02; H02K23/04; H02K23/40; H02K23/42

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 64 words
A split-pole structure for a permanent magnet motor having a rotating armature, comprising two circumferentially separated pole portions, one portion being a permanent magnet pole core of low permeability and the other portion being a magnetically conducting pole core of relatively high permeability, said portion of high permeability being located adjacent to and leading said permanent magnet portion in the direction of armature rotation.
Claim 2
Dependent Claim 64 words
A split-pole structure for a permanent magnet motor having a rotating armature, comprising two circumferentially separated pole portions, one portion being a permanent magnet pole core of low permeability and the other portion being a magnetically conducting pole core of relatively high permeability, said portion of high permeability being located adjacent to and leading said permanent magnet portion in the direction of armature rotation.
Claim 3
Dependent Claim 33 words
A split-pole structure in accordance with claim 1 in which the permanent magnet pole core is made of ceramic ferrite material and the magnetically conducting pole core is made of armature grade steel.
Claim 4
Dependent Claim 99 words
A permanent magnet electric motor comprising the combination of: an annular yoke of magnetic material; permanently magnetized pole cores of ceramic ferrite material mounted on an inwardly facing surface of said yoke and having pole faces directed radially toward the center of said yoke; an armature with circumferentially spaced conductors thereon mounted to rotate within said yoke and between said pole cores; and steel pole cores of relatively high permeability extending radially inwardly from the yoke and positioned adjacent to but separated from the permanently magnetized pole cores on the leading sides thereof in the direction of armature rotation.
Claim 5
Dependent Claim 99 words
A permanent magnet electric motor comprising the combination of: an annular yoke of magnetic material; permanently magnetized pole cores of ceramic ferrite material mounted on an inwardly facing surface of said yoke and having pole faces directed radially toward the center of said yoke; an armature with circumferentially spaced conductors thereon mounted to rotate within said yoke and between said pole cores; and steel pole cores of relatively high permeability extending radially inwardly from the yoke and positioned adjacent to but separated from the permanently magnetized pole cores on the leading sides thereof in the direction of armature rotation.
Claim 6
Dependent Claim 100 words
A permanent magnet electric motor comprising; and magnetic yoke having permanent magnet pole cores of relatively low permeability providing the main flux field, an armature winding mounted for rotation in said flux field, means providing current flow in said armature winding to produce said rotation, and magnetically conducting pole cores Of relatively high permeability located adjacent to the permanent magnet poles on the side thereof leading in the direction of armature rotation, said magnetically conducting pole cores providing a preferred path for the flux produced by the armature current and in a direction to add to the main field flux.
Claim 7
Dependent Claim 100 words
A permanent magnet electric motor comprising; and magnetic yoke having permanent magnet pole cores of relatively low permeability providing the main flux field, an armature winding mounted for rotation in said flux field, means providing current flow in said armature winding to produce said rotation, and magnetically conducting pole cores Of relatively high permeability located adjacent to the permanent magnet poles on the side thereof leading in the direction of armature rotation, said magnetically conducting pole cores providing a preferred path for the flux produced by the armature current and in a direction to add to the main field flux.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-03-01 1974-08-31 1975-03-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-03-01 1978-08-31 1979-03-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-03-01 1982-08-31 1983-03-02 $7700.00 Window Closed / Lapsed

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