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Coil arrangement for producing a homogeneous magnetic field

Assignee: Instrumentarium Oyj
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Filing: 1984-05-14
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Granted: 1987-02-17
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Expires: 2004-05-14
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Abstract

Abstract The invention relates to a coil arrangement for producing a homogeneous magnetic field especially for application to so-called NMR-imaging. An object of the invention is in terms of the size of a coil arrangement to expand the homogeneous area produced by a coil arrangement and, at the same time, to maintain the design of a coil arrangement simple and its manufacturing costs low. According to the invention, a coil arrangement includes three solenoids having a common axis, of which the axial winding width (W1) of the middlemost solenoid (1) is 2.75 . . . 2.95, preferably 2.835 . . . 2.855 times the mean radius (r1) of the middlemost solenoid (1) and the mean radius (r2) of the outermost solenoids (2) is 1.05 . . . 1.07, preferably 1.055 . . . 1.061 times the mean radius (r1) of the middlemost solenoid (1) and the axial winding width (W2) thereof is 0.32 . . . 0.38, preferably 0.340 . . . 0.342 times the mean radius (r1) of the middlemost solenoid (1). In addition, the distance (Z 1) from the center point of the outermost solenoids (2) to the center point of the middlemost solenoid (1) is 1.80 . . . 1.95, preferably 1.858 . . . 1.868 times the mean radius (r1) of the middlemost solenoid (1) and the electric current density of the middlemost solenoid (1) per unit length in the direction of the axial winding width is 0.250 . . . 0.275, preferably 0.2646 . . . 0.2666 times the electric current density of the outermost solenoids (2) measured in a corresponding manner.

Inventors

  • 👤 Matti Savelainen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 12:41
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/38; G01R33/381; G01R33/387; G01R33/3875

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 196 words
A coil arrangement for producing a homogeneous magnetic field especially for application to the so called NMR (nuclear magnetic resonance)-imaging, characterized in, that the coil arrangement includes three solenoids having a common axis, of which the axial winding width (W1) of the middlemost solenoid (1) is 2.75 . . . 2.95 times the mean winding radius (r1) of the middlemost solenoid (1), and the mean winding radius (r2) of the outermost solenoids (2) is 1.05 . . . 1.07 times the mean winding radius (r1) of the middlemost solenoid (1) and the axial winding width (w2) thereof is 0.32 . . . 0.38 times the mean winding radius (r1) of the middlemost solenoid (1), that additionally the distance (Z1) from the center point of the outermost solenoids (2) to the center point of the middlemost solenoid (1) is 1.80 . . . 1.95 times the mean winding radius (r1) of the middlemost solenoid (1) and that the electric current density of the middlemost solenoid (1) per unit length in the direction of the axial winding width is 0.250 . . . 0.275 times the electric current density of the outermost solenoids (2) in a corresponding manner.
Claim 2
Dependent Claim 196 words
A coil arrangement for producing a homogeneous magnetic field especially for application to the so called NMR (nuclear magnetic resonance)-imaging, characterized in, that the coil arrangement includes three solenoids having a common axis, of which the axial winding width (W1) of the middlemost solenoid (1) is 2.75 . . . 2.95 times the mean winding radius (r1) of the middlemost solenoid (1), and the mean winding radius (r2) of the outermost solenoids (2) is 1.05 . . . 1.07 times the mean winding radius (r1) of the middlemost solenoid (1) and the axial winding width (w2) thereof is 0.32 . . . 0.38 times the mean winding radius (r1) of the middlemost solenoid (1), that additionally the distance (Z1) from the center point of the outermost solenoids (2) to the center point of the middlemost solenoid (1) is 1.80 . . . 1.95 times the mean winding radius (r1) of the middlemost solenoid (1) and that the electric current density of the middlemost solenoid (1) per unit length in the direction of the axial winding width is 0.250 . . . 0.275 times the electric current density of the outermost solenoids (2) in a corresponding manner.
Claim 3
Dependent Claim 27 words
A coil arrangement as claimed in claim 1, characterized in, that said outermost solenoids (2) are displaceably connected to the middlemost solenoid (1) in the axial direction.
Claim 4
Dependent Claim 38 words
A coil arrangement as claimed in claim 1, characterized in, that the radial winding height (h2) of the outermost solenoids (2) is 3.5 . . . 3.9 times the radial winding height (h1) of the middlemost solenoid (1).
Claim 5
Dependent Claim 38 words
A coil arrangement as claimed in claim 1, characterized in, that the radial winding height (h2) of the outermost solenoids (2) is 0.13 . . . 0.16 times the mean (winding) radius (r1) of the middlemost solenoid (1).
Claim 6
Dependent Claim 170 words
A coil arrangement as claimed in claim 1 characterized in that the axial winding width (W1) of the middlemost solenoid (1) is 2.835 . . . 2.855 times the mean winding radius (r1) of the middlemost solenoid (1), the mean winding radius (r2) of the outermost solenoids (2) is 1.055 . . . 1.061 times the mean winding radius (r1) of the middlemost solenoid, the axial winding width (w2) of the outermost solenoids (2) is 0.340 . . . 0.342 times the mean winding radius (r1) of the middlemost solenoid (1), the distance (Z1) from the centerpoint of the outermost solenoids (2) to the centerpoint of the middlemost solenoid (1) is 1.858 . . . 1.868 times the mean winding radius (r1) of the middlemost solenoid (1) and that the electric current density of the middlemost solenoid (1) per unit length in the direction of the axial winding width is 0.2645 . . . 0.2666 times the electric current density of the outermost solenoids (2) measured in a corresponding manner.

References Cited (Backward Citations)

US4095202A Cited
US4320342A Cited
US4276529A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-02-16 1990-08-18 1991-02-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-02-16 1994-08-18 1995-02-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-02-16 1998-08-18 1999-02-17 $7700.00 Window Closed / Lapsed

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