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Patent US5631618A successfully refreshed from Google Patents.
US5631618A
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Magnetic arrays
Assignee: Massachusetts Institute of Technology
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Filing: 1994-09-30
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Granted: 1997-05-20
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Expires: 2014-09-30
Abstract
Abstract Electromagnet arrays which can provide selected field patterns in either two or three dimensions, and in particular, which can provide single-sided field patterns in two or three dimensions. These features are achieved by providing arrays which have current densities that vary in the windings both parallel to the array and in the direction of array thickness.
Inventors
- 👤 David L. Trumper
- 👤 Won-jong Kim
- 👤 Mark E. Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:50
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70691; G03F7/70758; H; H01; H01F; H01F7/00; H01F7/06; H01F7/20
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
80 words
An electromagnet array which extends in a first direction and has a thickness dimension in a second direction the second direction being normal to the first direction, the array comprising: a plurality of adjacent electromagnet segments which extend in at least one dimension having a selected winding pattern; and means for selectively applying varying current to said electromagnet segment windings; said winding patterns being such that the current density for the segments varies in both the first and second directions.
Claim 2
Dependent Claim
80 words
An electromagnet array which extends in a first direction and has a thickness dimension in a second direction the second direction being normal to the first direction, the array comprising: a plurality of adjacent electromagnet segments which extend in at least one dimension having a selected winding pattern; and means for selectively applying varying current to said electromagnet segment windings; said winding patterns being such that the current density for the segments varies in both the first and second directions.
Claim 3
Dependent Claim
29 words
An electromagnet array as claimed in claim 1 wherein said means for selectively applying current to said electromagnet segment windings applies current to the windings in a predetermined sequence.
Claim 4
Dependent Claim
40 words
An electromagnet array as claimed in claim 1 wherein each of said segments has windings in at least two different phases, and wherein said means for selectively applying current applies appropriate currents to the windings for each of said phases.
Claim 5
Dependent Claim
55 words
An electromagnet array as claimed in claim 3 wherein selected magnetic forces are to be provided in both the first and second directions, and wherein the means for selectively applying current includes means for controlling the magnitude of the current applied to each phase of each section so as to achieve the selected magnetic forces.
Claim 6
Dependent Claim
46 words
An electromagnet array as claimed in claim 1 wherein each of said electromagnet segments has a winding pattern which are determined as a selected set of sinusoidal variations in at least one dimension perpendicular to said first direction, whereby a desired field pattern may be achieved.
Claim 7
Dependent Claim
28 words
An electromagnet array as claimed in claim 5 wherein said winding patterns are triangular to provide a field which is substantially limited to one side of the array.
Claim 8
Dependent Claim
44 words
An electromagnet array as claimed in claim 1 wherein said means for selectively applying current includes means for reversing the direction in which said current flows for at least selected ones of said segments, whereby the direction of the magnetic field may be reversed.
Claim 9
Dependent Claim
48 words
An electromagnet array as claimed in claim 1 wherein each of said electromagnet segments has windings of a material which is superconducting below a selected temperature, and means for maintaining the windings for at least the segments to which current is being selectively applied below said selected temperature.
Claim 10
Dependent Claim
18 words
An electromagnet array as claimed in claim 8 including electromagnetic means interacting with said array to provide mag-lift.
Claim 11
Dependent Claim
41 words
An electromagnet array as claimed in claim 1 wherein each electromagnet segment has a magnetic orientation about an axis perpendicular to said first and second directions which is rotated by a selected angle from the orientation of each adjacent electromagnet segment.
Claim 12
Dependent Claim
28 words
An electromagnet array as claimed in claim 10 wherein the angle of rotation and the direction of rotation are the same for each adjacent pair of electromagnet segments.
Claim 13
Dependent Claim
27 words
An electromagnet array as claimed in claim 10 wherein the selected angle by which the magnetic orientation is rotated between adjacent segments is not more than 90°.
Claim 14
Dependent Claim
54 words
An electromagnet array as claimed in claim 1 wherein said array extends in two dimensions, being formed of a matrix of rows and columns of electromagnet segments, with each electromagnet segment having a three dimensional magnetic orientation which is the sum of the magnetic orientations for the segment for its corresponding row and column.
Claim 15
Dependent Claim
163 words
A two-dimensional magnetic array comprising: a plurality of magnet segments arranged in a two-dimensional matrix array of rows and columns, with each segment having at least one adjacent row segment and at least one adjacent column segment, each of said segments having a three dimensional magnetic orientation which is the vector sum of a nominal magnetic orientation for the segment's row and a nominal magnetic orientation for the segment's column, adjacent segments in each column having a nominal magnetic orientation about a row axis which is rotated in a selected direction by an angle of not more than 90° in a selected direction from the nominal column magnetic orientation of each adjacent segment in the column, and adjacent segments in each row having a nominal magnetic orientation about a column axis which is rotated in a selected direction by an angle of not more than 90° in a selected direction from the nominal row magnetic orientation of each adjacent segment in the row.
Claim 16
Dependent Claim
163 words
A two-dimensional magnetic array comprising: a plurality of magnet segments arranged in a two-dimensional matrix array of rows and columns, with each segment having at least one adjacent row segment and at least one adjacent column segment, each of said segments having a three dimensional magnetic orientation which is the vector sum of a nominal magnetic orientation for the segment's row and a nominal magnetic orientation for the segment's column, adjacent segments in each column having a nominal magnetic orientation about a row axis which is rotated in a selected direction by an angle of not more than 90° in a selected direction from the nominal column magnetic orientation of each adjacent segment in the column, and adjacent segments in each row having a nominal magnetic orientation about a column axis which is rotated in a selected direction by an angle of not more than 90° in a selected direction from the nominal row magnetic orientation of each adjacent segment in the row.
Claim 17
Dependent Claim
19 words
A magnetic array as claimed in claim 12 wherein each of said magnet segments is a permanent magnet segment.
Claim 18
Dependent Claim
80 words
An electromagnet array which extends in a first direction and has a thickness dimension in a second direction the second direction being normal to the first direction, the array comprising: a repetitive pattern of electromagnet windings; and means for selectively applying varying current to said windings; the pattern of the windings being such that when current is applied thereto, the current density in the windings varies in both the first and the second directions as a selected sum of sinusoids.
Claim 19
Dependent Claim
80 words
An electromagnet array which extends in a first direction and has a thickness dimension in a second direction the second direction being normal to the first direction, the array comprising: a repetitive pattern of electromagnet windings; and means for selectively applying varying current to said windings; the pattern of the windings being such that when current is applied thereto, the current density in the windings varies in both the first and the second directions as a selected sum of sinusoids.
References Cited (Backward Citations)
US3531744A
Cited
US4878024A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2000-05-19 | 2000-11-18 | 2001-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-05-19 | 2004-11-18 | 2005-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-05-19 | 2008-11-18 | 2009-05-20 | $7700.00 | Window Closed / Lapsed |