US3918016A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically conductive plates providing eddy current damping for an electro-magnetic device
Assignee: ZF International UK Ltd
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Filing: 1974-11-25
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Granted: 1975-11-04
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Expires: 1994-11-25
Abstract
Abstract A torque motor comprises a frame including a pair of opposed and spaced side members formed from a material having a high magnetic permeability. A cavity is defined between the members in which is mounted a pivotal permanent magnet, the cavity also including a winding so that when the winding is energised, the magnet will tend to turn about the pivotal axis. The side members are interconnected at their side edges by a pair of plate members formed from electrically conductive but non-magnetic material, the plate members acting to provide eddy current damping when the magnet is moved relative to the frame.
Inventors
- 👤 George Frankl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:09
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/14
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
115 words
An electromagnetic device comprising a frame including a pair of opposed and spaced side members formed from a material having a high magnetic permeability and defining an internal cavity, a permanent magnet pivotally mounted within the cavity and a winding mounted within the cavity whereby when the winding is energised the magnet will tend to turn about its pivot axis so that its magnetic axis will be aligned with that of the winding characterised in that the side members are interconnected at their side edges by a pair of plate members formed from electrically conductive non-magnetic material, said plate members acting to provide eddy current damping when the magnet is moved relative to the frame.
Claim 2
Dependent Claim
115 words
An electromagnetic device comprising a frame including a pair of opposed and spaced side members formed from a material having a high magnetic permeability and defining an internal cavity, a permanent magnet pivotally mounted within the cavity and a winding mounted within the cavity whereby when the winding is energised the magnet will tend to turn about its pivot axis so that its magnetic axis will be aligned with that of the winding characterised in that the side members are interconnected at their side edges by a pair of plate members formed from electrically conductive non-magnetic material, said plate members acting to provide eddy current damping when the magnet is moved relative to the frame.
Claim 3
Dependent Claim
29 words
A device according to claim 1 characterised in that the end edges of the side members are interconnected by end members, said end members defining bearings for the rotor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |