US5402025A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotor provided with a ring-shaped magnet
Assignee: Daido Steel Co Ltd
•
Filing: 1993-12-17
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Granted: 1995-03-28
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Expires: 2013-12-17
Abstract
Abstract A rotor comprises a rotor body and a ring-shaped rare earth metal-iron type magnet arranged therearound, in which a low thermal-expansion material is inserted between the rotor body and the magnet.
Inventors
- 👤 Makoto Saito
- 👤 Yasuaki Kasai
- 👤 Hiyoshi Yamada
- 👤 Norio Yoshikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:54
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/22; H02K1/27; H02K1/2706; H02K1/272; H02K1/2726; H02K1/2733
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
75 words
A rotor comprising a rotor body, a ring-shaped rare earth metal-iron type magnet arranged around the rotor body, and a low thermal-expansion material inserted between said rotor body and the magnet, wherein said rotor body has a thermal expansion coefficient of 8-25×10 -6/ °C., said magnet has a thermal expansion coefficient of not more than 3×10 -6 /°C., and said low thermal-expansion material has a thermal expansion coefficient of not more than 5×10 -6 /°C.
Claim 2
Dependent Claim
75 words
A rotor comprising a rotor body, a ring-shaped rare earth metal-iron type magnet arranged around the rotor body, and a low thermal-expansion material inserted between said rotor body and the magnet, wherein said rotor body has a thermal expansion coefficient of 8-25×10 -6/ °C., said magnet has a thermal expansion coefficient of not more than 3×10 -6 /°C., and said low thermal-expansion material has a thermal expansion coefficient of not more than 5×10 -6 /°C.
Claim 3
Dependent Claim
24 words
A rotor as set forth in claim 1, wherein a further low thermal-expansion material is arranged on an outer peripheral surface of said magnet.
Claim 4
Dependent Claim
75 words
A rotor comprising a rotor body, a ring-shaped rare earth metal-iron type magnet arranged around the rotor body, and a low thermal-expansion material inserted between said rotor body and the magnet, wherein said rotor body has a thermal expansion coefficient of 10-20×10 -6 /°C., said magnet has a thermal- expansion coefficient of not more than 3×10 -6 /°C., and said low thermal-expansion material has a thermal expansion coefficient of not more than 5×10 -6 /°C.
Claim 5
Dependent Claim
75 words
A rotor comprising a rotor body, a ring-shaped rare earth metal-iron type magnet arranged around the rotor body, and a low thermal-expansion material inserted between said rotor body and the magnet, wherein said rotor body has a thermal expansion coefficient of 10-20×10 -6 /°C., said magnet has a thermal- expansion coefficient of not more than 3×10 -6 /°C., and said low thermal-expansion material has a thermal expansion coefficient of not more than 5×10 -6 /°C.
Claim 6
Dependent Claim
24 words
A rotor as set forth in claim 3, wherein a further low thermal-expansion material is arranged on an outer peripheral surface of said magnet.
References Cited (Backward Citations)
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Cited
US3914629A
Cited
US4625135A
Cited
US4874975A
Cited
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US5142180A
Cited
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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) | 1998-03-27 | 1998-09-26 | 1999-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-27 | 2002-09-26 | 2003-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-27 | 2006-09-26 | 2007-03-28 | $7700.00 | Window Closed / Lapsed |