Patent US4579879A successfully refreshed from Google Patents.
Patent US3779618A successfully refreshed from Google Patents.
US3779618A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-centering magnetic suspension
Assignee: National Agency for New Technologies, Energy and Sustainable Economic Development
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Filing: 1972-02-24
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Granted: 1973-12-18
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Expires: 1992-02-24
Abstract
Abstract A device is provided for magnetically suspending a body which rotates about a vertical axis for centering said body radially with respect to said axis and for maintaining it at a constant height which device comprises a magnet which provides the main suspension force, a round armature fastened to the suspended body under said magnet which armature is provided with a peripheral tapered ridge for producing a radial return force when this armature moves radially with respect to a tapered circular pole piece of said magnet and with a series of disks each interposed between a pair of coils for producing the vertical balancing force as required for keeping the rotating load at a predetermined level.
Inventors
- 👤 Marino C Di
- 👤 G Sacerdoti
- 👤 L Soglia
- 👤 A Catitti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:50
CPC Classifications
F; F16; F16C; F16C32/00; F16C32/04; F16C32/0406; F16C32/0408; F16C32/041; F16C32/0412; F16C32/0414; F16C32/0417; F16C32/0436; F16C39/00; F16C39/06; F16C39/063
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
318 words
A device for suspending a load by means of magnetic forces at a predetermined level and for centering it with respect to a vertical axis and keeping it mechanically separated in operation from the surrounding structure by a space which may be filled with a fluid, which device comprises a stationary circular cylindrical body with vertical axis and horizontal bases in which body a toroidal recess is provided extending from the bottom base upward for a distance shorter than the body height whereby a cuplike shape is obtained of said body with a central cylindrical boss and outer cylindrical skirt, the lower ends of said boss and skirt being substantially at the same level, said skirt terminating with a downwardly pointing tapered edge; said cylindrical body being made of ferromagnetic material; a permanent magnet being incorporated therewith to provide a magnetic field of which the pole pieces are the circular tapered edge of said skirt and the bottom end of said boss; which device comprises a disk shaped armature fastened to said load and provided on its upper surface with a central projection aligned with said cylindrical boss and having substantially the same diameter and with a peripheral tapered ridge aligned with the tapered edge of said skirt; the upper surface of said central projection and peripheral ridge being separated in operation from the confronting surface of said cylindrical bell-shaped body by an air gap; which device comprises aLso at least one disk-shaped horizontal body of electricity conducting material coaxial with said armature and fastened thereto; each disk-shaped body being interposed between two annular horizontal coils mounted on a stationary support and excited by an external power source; the force for suspending the weight of load and of the structural components connected thereto being provided for a major portion by said permanent magnet while the difference between said weight and the magnet force is provided by said coils.
Claim 2
Independent Claim
318 words
A device for suspending a load by means of magnetic forces at a predetermined level and for centering it with respect to a vertical axis and keeping it mechanically separated in operation from the surrounding structure by a space which may be filled with a fluid, which device comprises a stationary circular cylindrical body with vertical axis and horizontal bases in which body a toroidal recess is provided extending from the bottom base upward for a distance shorter than the body height whereby a cuplike shape is obtained of said body with a central cylindrical boss and outer cylindrical skirt, the lower ends of said boss and skirt being substantially at the same level, said skirt terminating with a downwardly pointing tapered edge; said cylindrical body being made of ferromagnetic material; a permanent magnet being incorporated therewith to provide a magnetic field of which the pole pieces are the circular tapered edge of said skirt and the bottom end of said boss; which device comprises a disk shaped armature fastened to said load and provided on its upper surface with a central projection aligned with said cylindrical boss and having substantially the same diameter and with a peripheral tapered ridge aligned with the tapered edge of said skirt; the upper surface of said central projection and peripheral ridge being separated in operation from the confronting surface of said cylindrical bell-shaped body by an air gap; which device comprises aLso at least one disk-shaped horizontal body of electricity conducting material coaxial with said armature and fastened thereto; each disk-shaped body being interposed between two annular horizontal coils mounted on a stationary support and excited by an external power source; the force for suspending the weight of load and of the structural components connected thereto being provided for a major portion by said permanent magnet while the difference between said weight and the magnet force is provided by said coils.
Claim 3
Dependent Claim
157 words
A device as claimed in claim 1, in which device said electric coils of annular form are stacked and coaxial one to the others and said electricity conducting metal bodies are circular and flat each of them being interposed between two of said coils; a separation space being left between the body and the adjacent coils whereby eddy currents are induced on said conducting bodies when said coils are energized with electric current; said armature being provided on its face confronting the permanent magnet with circular concentric projections which are aligned with the inner and outer circular pole pieces of the magnet and related support skirt; said device being further provided with two circular flat shields made of electricity conducting material which are placed above and below the coils stack with the purpose of preventing the magnetic flux generated by the coils from invading the space surrounding the assembly of the conducting bodies and of the coils.
Claim 4
Dependent Claim
185 words
A suspension device as claimed in claim 1, wherein said permanent magnet has the form of a right circular cylinder with vertical axis and strongly tapered at its lower portion, while its top base joins the bottom end of a ferromagnetic support which also has the form of a right circular cylinder and preferably the same cross section as the top base of the magnet, which support at its upper end extends horizontally for a distance and then vertically downwards to form a skirt which reaches the level of the bottom end of the magnet with a strongly tapered edge whereby an annular downwardly open space is defined between said cylindrical portion and said skirt portion of said support; in which device said armature is in the form of a disk from the upper surface of which a central circular boss and a tapered peripheral ridge project upwards to face respectively the bottom base of the magnet and the edge of said support skirt; said boss and ridge being separated in operation from the corresponding surfaces of said magnet and skirt by an air gap.
Claim 5
Dependent Claim
112 words
A device as claimed in claim 3 wherein said central cylindrical portion of said support is connected to the horizontally extending portion of the same support by a screw thread provided on the side surface of said cylindrical portion which screw thread engages a corresponding screw threading of a central bore provided through said horizontal portion a cuplike member being provided for firmly connecting the latter to said horizontal support portion, whereby the bottom end of the support cylindrical portion can be adjustably moved towards and away from the top magnet base and the strength of the magnetic flux can be adjusted without changing the relative positions of the magnet and armature.
Claim 6
Dependent Claim
97 words
A device for suspending a load and maintaining it centered with respect to a vertical axis, as claimed in claim 1, wherein said permanent magnet has the form of a ring coaxial with said body of ferromagnetic material which ring occupies the lower portion of the outer wall of said body and is fastened to the rest of the same wall; its cross section being trapezium-shaped with a horizontal side equal to the wall thickness and the opposed side very short and substantially equal to the width of the confronting top face of the armature peripheral ridge.
Claim 7
Dependent Claim
86 words
A device as claimed in claim 5 wherein said permanent magnet has the form of a ring coaxial with said body of ferromagnetic material which ring occupies the lower portion of the outer wall of said body and separated by aN adjustable air gap therefrom said magnet being fastened to a stationary support while the rest of said outer wall can be moved up and down with respect to the stationary central portion of said ferromagnetic body by means of the screw threaded engagement between them.
Claim 8
Dependent Claim
42 words
A device as claimed in claim 1 wherein a cylindrical bore coaxial with said cylindrical body and in operation with said armature and said disk-shaped bodies is provided for giving access to the suspended load from the top of the suspension device.
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) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |