Patent US3612929A successfully refreshed from Google Patents.
US3612929A
Expired / Lapsed
US
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Device for temperature compensation in electrical machines excited by permanent magnets
Assignee: Siemens AG
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Filing: 1969-09-19
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Granted: 1971-10-12
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Expires: 1989-09-19
Abstract
Abstract An electrical machine, with a stator and a rotor of which one has permanent-magnet means for exciting the machine, is provided with a device for temperature compensation of the magnetic stray flux. The device comprises bimetal structure subject to the operational heat of the machine and adapted to temperatureresponsively control the stray flux. Preferably, the bimetal structure consists of one or more flat bimetal members disposed in the region of the magnetic stray flux so that temperature increase causes being of the bimetal member which then increases the width of an airgap to reduce the stray flux.
Inventors
- 👤 Wolfgang Volkrodt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:55
CPC Classifications
H; H02; H02K; H02K23/00; H02K23/40; H02K23/44; H02K1/00; H02K1/06; H02K1/22; H02K1/27; H02K1/2706; H02K1/272; H02K1/2726; H02K23/02; H02K23/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
101 words
With an electrical machine having a stator member and a rotor member of which one has permanent-magnet means for exciting magnetic flux in said members, the combination of a device for temperature compensation of magnetic stray flux comprising a flat bimetal structure subject to operational heat of the machine, said structure being mounted on at least one of said members in the region of the magnetic stray flux so that the temperature increase causes bending of the bimetal member, said structure forming, when bent, an airgap with said member whose width increases with temperature so as to reduce the stray flux.
Claim 2
Dependent Claim
101 words
With an electrical machine having a stator member and a rotor member of which one has permanent-magnet means for exciting magnetic flux in said members, the combination of a device for temperature compensation of magnetic stray flux comprising a flat bimetal structure subject to operational heat of the machine, said structure being mounted on at least one of said members in the region of the magnetic stray flux so that the temperature increase causes bending of the bimetal member, said structure forming, when bent, an airgap with said member whose width increases with temperature so as to reduce the stray flux.
Claim 3
Dependent Claim
36 words
In a machine according to claim 1, said magnet means comprising permanent magnets built into said rotor, and said bimetal member comprising a disc of ferromagnetic bimetal on at least one end face of said rotor.
Claim 4
Dependent Claim
47 words
In a machine according to claim 1, said stator having salient poles and said magnet means being formed of shell-type permanent magnets of ferrite mounted on said stator, said bimetal structure comprising stray-flux strips of ferromagnetic bimetal arranged on at least one end face of said stator.
Claim 5
Dependent Claim
66 words
In a machine according to claim 1, said magnet means comprising permanent-magnet blocks built into said stator and having stray paths between said blocks, said stray paths being formed of plunger-type armatures mounted and radially displaceable between each two adjacent ones of said blocks, a stator magnetizable yoke surrounding said blocks, said bimetal structure comprising bimetal plates interPosed between said respective armatures and said stator yoke.
References Cited (Backward Citations)
US1895049A
Cited
US2058339A
Cited
US2191074A
Cited
US2720603A
Cited
US3200276A
Cited
US3214620A
Cited
US3720604A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |