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US4808957A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic shield apparatus

Assignee: Toshiba Corp
•
Filing: 1988-06-08
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Granted: 1989-02-28
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Expires: 2008-06-08
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Abstract

Abstract A magnetic shield apparatus for shielding against magnetic leakage escaping from a cylindrical magnet unit having a columnar cavity, for generating a static magnetic field along the axial direction of the cavity, has a plurality of magnetic shield members which shield against magnetic leakage escaping from the magnet unit. The magnetic shield members are sequentially joined, with the joint portions of the magnetic shield members extending along the axial direction of the cavity, so as to surround the magnet unit. Casters are attached to each magnetic shield member. The magnetic shield members are fixed by bolts or the like so as to surround the magnet unit.

Inventors

  • 👤 Hiroshi Furukawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 03:53
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/42; G01R33/421

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 124 words
A magnetic shield apparatus for shielding against magnetic leakage escaping from cylindrical magnetic field generating means having a columnar cavity, for generating a static magnetic field along an axial direction of said cavity, said magnetic shield apparatus comprising: a plurality of magnetic shielding means for shielding against magnetic leakage escaping from said magnetic field generating means, said plurality of magnetic shielding means being sequentially joined, with the joint portions thereof extending along the axial direction of said cavity, so as to surround said magnetic field generating means; a plurality of movable means supporting said plurality of magnetic shielding means, respectively; and fixing means for fixing said magnetic shielding means in such a way that said magnetic shielding means surround said magnetic field generating means.
Claim 2
Dependent Claim 124 words
A magnetic shield apparatus for shielding against magnetic leakage escaping from cylindrical magnetic field generating means having a columnar cavity, for generating a static magnetic field along an axial direction of said cavity, said magnetic shield apparatus comprising: a plurality of magnetic shielding means for shielding against magnetic leakage escaping from said magnetic field generating means, said plurality of magnetic shielding means being sequentially joined, with the joint portions thereof extending along the axial direction of said cavity, so as to surround said magnetic field generating means; a plurality of movable means supporting said plurality of magnetic shielding means, respectively; and fixing means for fixing said magnetic shielding means in such a way that said magnetic shielding means surround said magnetic field generating means.
Claim 3
Dependent Claim 36 words
The apparatus according to claim 1, wherein said magnetic shielding means comprise two pairs of edges which extend along the axial direction of said cavity, the adjacent edges of said two pairs of edges being joined.
Claim 4
Dependent Claim 21 words
The apparatus according to claim 1, wherein said magnetic shielding means comprise magnetic shield members each having a semicircular cross section.
Claim 5
Dependent Claim 30 words
The apparatus according to claim 1, wherein said magnetic shielding means comprise magnetic shield members each having a semicircular cross section obtained by cutting a cylinder in a vertical direction.
Claim 6
Dependent Claim 24 words
The apparatus according to claim 1, wherein said movable members comprise legs coupled to said magnetic shielding means and casters attached to said legs.
Claim 7
Dependent Claim 40 words
The apparatus according to claim 1, wherein said fixing means comprise first fixing means for fixing said magnetic shielding means to one another and second fixing means for fixing said magnetic shielding means to a surface of an installation floor.
Claim 8
Dependent Claim 111 words
A magnet unit comprising: cylindrical magnetic field generating means, having a columnar cavity, for generating a static magnetic field along an axial direction of said cavity; a plurality of magnetic shielding means for shielding against magnetic leakage escaping from said magnetic field generating means, said plurality of magnetic shielding means being sequentially joined, with joint portions thereof extending along the axial direction of said cavity, so as to surround said magnetic field generating means; a plurality of movable means supporting said plurality of magnetic shielding means, respectively; and fixing means for fixing said magnetic shielding means in such a way that said magnetic shielding means surround said magnetic field generating means.
Claim 9
Dependent Claim 111 words
A magnet unit comprising: cylindrical magnetic field generating means, having a columnar cavity, for generating a static magnetic field along an axial direction of said cavity; a plurality of magnetic shielding means for shielding against magnetic leakage escaping from said magnetic field generating means, said plurality of magnetic shielding means being sequentially joined, with joint portions thereof extending along the axial direction of said cavity, so as to surround said magnetic field generating means; a plurality of movable means supporting said plurality of magnetic shielding means, respectively; and fixing means for fixing said magnetic shielding means in such a way that said magnetic shielding means surround said magnetic field generating means.

References Cited (Backward Citations)

US3437963A Cited
US3460083A Cited
US4490675A Cited
US4646045A Cited
US4758812A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-02-28 1992-08-29 1993-02-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-02-28 1996-08-29 1997-02-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-02-28 2000-08-29 2001-02-28 $7700.00 Window Closed / Lapsed

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