US4385280A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low reluctance latching magnets
Assignee: MAUFACTURING MINING & MANUFACTURING Co
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Filing: 1981-03-23
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Granted: 1983-05-24
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Expires: 2001-03-23
Abstract
Abstract An electromagnetic device having an armature mounted in the gap of a ferromagnetic core for selective contact of either of opposed pole faces. A source of latching flux retains the armature in contact with either of the pole faces while a flux return bracket conducts flux between the armature and the source of latching flux. The source of latching flux has a surface area perpendicular to the flux path greater than the length along the flux path creating a low reluctance path for a portion of the operating flux.
Inventors
- 👤 Daniel E. Reisem
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:10
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01H; H01H50/00; H01H50/16
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
132 words
An electromagnetic device comprising: a ferromagnetic core having opposed pole faces defining a gap; a source of operating flux for establishing a magnetic field in said gap; an armature mounted for selective contact with either of said pole faces; a source of latching flux for retaining said armature in contact with either of said pole faces; and a flux return bracket contacting said source of latching flux and contacting said armature for conducting flux therebetween; said source of latching flux having a surface area A perpendicular to the flux path and a length L along the flux path such that the factor L/A is less than 1, whereby said source of latching flux, said flux return bracket, and said armature provides a low reluctance path for a portion of the operating flux.
Claim 2
Dependent Claim
132 words
An electromagnetic device comprising: a ferromagnetic core having opposed pole faces defining a gap; a source of operating flux for establishing a magnetic field in said gap; an armature mounted for selective contact with either of said pole faces; a source of latching flux for retaining said armature in contact with either of said pole faces; and a flux return bracket contacting said source of latching flux and contacting said armature for conducting flux therebetween; said source of latching flux having a surface area A perpendicular to the flux path and a length L along the flux path such that the factor L/A is less than 1, whereby said source of latching flux, said flux return bracket, and said armature provides a low reluctance path for a portion of the operating flux.
Claim 3
Dependent Claim
17 words
An electromagnetic device as in claim 1 wherein said source of latching flux comprises a permanent magnet.
Claim 4
Dependent Claim
22 words
An electromagnetic device as in claim 2 wherein said permanent magnet comprises domain size ferrite particles dispersed in a flexible nonmagnetic binder.
Claim 5
Dependent Claim
17 words
An electromagnetic device as in claim 2 further comprising a load switch mechanically actuated by said armature.
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) | 1986-05-23 | 1986-11-22 | 1987-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-23 | 1990-11-22 | 1991-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-23 | 1994-11-22 | 1995-05-24 | $7700.00 | Window Closed / Lapsed |