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US4672252A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrical machine with a stator lamination of grain-oriented sheets

Assignee: Siemens AG
•
Filing: 1981-02-13
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Granted: 1987-06-09
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Expires: 2001-02-13
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Abstract

Abstract The laminations of a laminated stator of a slowly running electrical machine having a high number of poles are composed of grain-oriented sheets, each of which has a preferential magnetic direction that extends substantially longitudinally along the teeth of that sheet. This permits the excitation current to be reduced, and, as a result, the air gap of the machine can be enlarged so that, on the whole, approximately the same excitation is required as for a laminated stator in which the laminations consist of normal, non-oriented sheets. As a result, the mechanical stability of the machine is increased. The invention is especially useful in asynchronous tube generators.

Inventors

  • 👤 Franz Spirk

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 09:48
CPC Classifications
H; H02; H02K; H02K19/00; H02K19/16; H02K19/22; H02K1/00; H02K1/02; H02K17/00; H02K17/42

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 138 words
In an electric machine having a stator lamination made up of grain-oriented sheets, each having a plurality of radially directed teeth, the radial direction of the teeth establishing a lengthwise direction, the direction of the grain orientation, in the area of the teeth, extending in the lengthwise direction of the teeth, said machine having a large number of poles, and adapted to run at a slow speed, the improvement comprising, the sheets making up the stator lamination having as their direction of grain orientation, throughout the sheet, a direction essentially corresponding to the lengthwise direction of the teeth and, the air gap in said machine enlarged to the extent that the excitation current requirements for the machine correspond to that of a stator lamination made up of normal, non-oriented sheets, thereby permitting increased mechanical stability in the machine.
Claim 2
Dependent Claim 138 words
In an electric machine having a stator lamination made up of grain-oriented sheets, each having a plurality of radially directed teeth, the radial direction of the teeth establishing a lengthwise direction, the direction of the grain orientation, in the area of the teeth, extending in the lengthwise direction of the teeth, said machine having a large number of poles, and adapted to run at a slow speed, the improvement comprising, the sheets making up the stator lamination having as their direction of grain orientation, throughout the sheet, a direction essentially corresponding to the lengthwise direction of the teeth and, the air gap in said machine enlarged to the extent that the excitation current requirements for the machine correspond to that of a stator lamination made up of normal, non-oriented sheets, thereby permitting increased mechanical stability in the machine.
Claim 3
Dependent Claim 23 words
The improvement according to claim 1, wherein said electric machine comprises slowly running asynchronous generator forming a part of a bulb turbine set.

References Cited (Backward Citations)

US2046717A Cited
US2433660A Cited
US2792511A Cited
US2774000A Cited
US2968860A Cited
US3809938A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-08 1990-12-08 1991-06-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-08 1994-12-08 1995-06-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-08 1998-12-08 1999-06-09 $7700.00 Window Closed / Lapsed

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