US3594595A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alternating current generators
Assignee: NAT RES DEV
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Filing: 1969-09-30
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Granted: 1971-07-20
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Expires: 1989-09-30
Abstract
Abstract An inductor alternator the stator member of which carries a DC excitation winding and an output winding, which may be multiphase, and a rotor member carrying a short-circuited winding. The short-circuited winding may be a squirrel cage or may comprise conductor bars connected in series with each other between end rings or else may be connected to form shortcircuited coils. The action of the machine is that circulating currents are generated in the rotor winding as the rotor rotates the direction of these currents reversing over pole pitches of the excitation winding and the multipole field so generated causes alternating currents to be generated in the output winding.
Inventors
- 👤 Frederic Calland Williams
- 👤 Graham Wilson Mclean
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:48
CPC Classifications
H; H02; H02K; H02K19/00; H02K19/16; H02K19/22; H02K19/24; H02K99/00; H02K99/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
167 words
An inductor alternator comprising: a rotatable nonsalient pole rotor member carrying a shortcircuited winding for generating a multipole magnetic field as a result of circulating currents within said short-circuited winding, a stator member disposed adjacent said rotor member and defining a circumferential airgap therebetween, said stator member having at least first and second predetermined positions spaced apart around said circumferential airgap, a DC excitation winding disposed within said stator member, said excitation winding having at least first and second sections respectively associated with said first and second positions such that, when energized with direct current of appropriate polarity, circulating currents produced in elements of said short-circuited rotor winding are caused to reverse in direction upon passing said predetermined positions thereby changing the magnetic polarity of portions of the rotor member directly associated with said element, and an AC output winding also disposed on said stator member between said first and second predetermined positions for energization with alternating current by said multipole field moving with said rotor member.
Claim 2
Dependent Claim
167 words
An inductor alternator comprising: a rotatable nonsalient pole rotor member carrying a shortcircuited winding for generating a multipole magnetic field as a result of circulating currents within said short-circuited winding, a stator member disposed adjacent said rotor member and defining a circumferential airgap therebetween, said stator member having at least first and second predetermined positions spaced apart around said circumferential airgap, a DC excitation winding disposed within said stator member, said excitation winding having at least first and second sections respectively associated with said first and second positions such that, when energized with direct current of appropriate polarity, circulating currents produced in elements of said short-circuited rotor winding are caused to reverse in direction upon passing said predetermined positions thereby changing the magnetic polarity of portions of the rotor member directly associated with said element, and an AC output winding also disposed on said stator member between said first and second predetermined positions for energization with alternating current by said multipole field moving with said rotor member.
Claim 3
Dependent Claim
29 words
An inductor alternator as in claim 1 wherein the rotor winDing comprises groups of conductor bars connected together in series and short-circuiting connections for said groups of conductor bars.
Claim 4
Dependent Claim
26 words
The alternator as claimed in claim 1 in which the rotor winding comprises a plurality of conductor bars spaced apart round the periphery of the rotor.
Claim 5
Dependent Claim
20 words
The alternator as claimed in claim 3 in which the ends of each bar are connected to short-circuited end rings.
Claim 6
Dependent Claim
28 words
The alternator as claimed in claim 1 in which the excitation winding is such that the distribution of conductive material around the circumference of the stator varies sinusoidally.
Claim 7
Dependent Claim
30 words
The alternator as claimed in claim 2 in which the short-circuiting connections of the rotor winding comprise end rings to which the series connected groups of conductor bars are connected.
Claim 8
Dependent Claim
30 words
The alternator as claimed in claim 2 in which the short-circuiting connections of the rotor windings are such that the series-connected groups of conductor bars each form separate short-circuited coils.
Claim 9
Dependent Claim
32 words
The alternator as claimed in claim 7 in which the DC excitation winding is limited to the region of said spaced-apart positions at which current reversal in the rotor windings takes place.
Claim 10
Dependent Claim
30 words
The alternator as claimed in claim 8 in which the stator is provided with additional windings in the form of short-circuited connections over the region of said current reversal positions.
Claim 11
Dependent Claim
16 words
The alternator as claimed in claim 9 in which the said additional windings comprise gridlike structures.
Claim 12
Dependent Claim
30 words
The alternator as claimed in claim 9 in which the airgap between the rotor member and the stator member is made larger over the region of said positions than elsewhere.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |