Gradient coil apparatus and methods for MRI

Patent metadata

Field	Value
Publication number	US-11821970-B2
Application number	US-202117645108-A
Country	US
Kind code	B2
Filing date	Dec 20, 2021
Priority date	Sep 13, 2019
Publication date	Nov 21, 2023
Grant date	Nov 21, 2023

Abstract

A coil apparatus and methods for magnetic resonance imaging involving a wire winding, the wire winding having at least one of: a hollow cross-section wire and a solid cross-section wire, the solid cross-section wire having at least one of: a solid small cross-section wire and a solid large cross-section wire, the solid large cross-section wire having a thickness greater than that of the solid small cross-section wire, and the solid small cross-section wire disposed in one of adjacent and proximate at least one of the hollow cross-section wire and the solid large cross-section wire, whereby at least one of current density, winding density, and heat extraction are increasable.

First claim

What is claimed:

1. A coil apparatus for magnetic resonance imaging, comprising:
at least one wire winding,
the at least one wire winding comprising at least one hollow cross-section wire and at least one solid cross-section wire,
the at least one solid cross-section wire disposed adjacent and proximate to the at least one hollow cross-section wire,
the at least one solid cross-section wire directed parallel to the at least one hollow cross-section wire along the path of the at least one wire winding,
the at least one wire winding configured to carry electrical current such that each of the at least one solid cross-section wire and each of the at least one hollow cross-section wire are electrically connected in series with each other and convey simultaneously the same electrical current,
an electrical power supply configured to drive electrical current through the at least one wire winding,
a liquid cooling source configured to flow liquid coolant through the at least one hollow cross-section wire continuously, and
whereby at least one of current density, winding density, and heat extraction are increasable,
wherein the at least one hollow cross-section wire comprises a plurality of hollow cross-section wires,
wherein the plurality of hollow cross-section wires comprises a set of hollow cross-section wires,
wherein each hollow cross-section wire of the set comprises a plurality of parallel manifolds for increasing total coolant flow rate, for a given pressure drop across the set, wherein heat extraction is increasable,
wherein the plurality of parallel manifolds facilitates electrical current flow from the set to one of an adjacent set and a proximate set of hollow cross-section wires,
wherein the plurality of parallel manifolds directs coolant flow in relation to a winding segment, and
wherein each parallel manifold of the plurality of parallel manifolds is configured to insert into each at least one hollow cross-section wire via a through-hole and to effect parallel coolant flow paths to reduce overall flow resistance and to improve cooling.

2. The apparatus of claim 1 , wherein at least one of:
the at least one solid cross-section wire comprises at least one solid small cross-section wire and at least one solid large cross-section wire,
the at least one solid large cross-section wire comprises a cross-section area greater than that of the at least one solid small cross-section wire,
the at least one solid small cross-section wire disposed in one of adjacent and proximate at least one of the at least one hollow cross-section wire and the at least one solid large cross-section wire,
the at least one wire winding comprises at least one portion, one portion comprising at least one of the at least one hollow cross-section wire and the at least one solid small cross-section wire, and another portion comprising at least one of the at least one hollow cross-section wire being spaced apart and the at least one solid small cross-section wire being spaced apart, and
the at least one wire winding is configured as one of a Z-gradient coil, a uniform field coil, and a Bd offset coil.

3. The apparatus of claim 1 , wherein the at least one solid cross-section wire comprises a width less than that of the at least one hollow cross-section wire.

4. The apparatus of claim 1 , wherein each at least one solid cross-section wire is disposed in one of adjacent and proximate two hollow cross-section wires.

5. The apparatus of claim 1 , wherein a plurality of solid cross-section wires are disposed in one of adjacent and proximate each at least one hollow cross-section wire.

6. The apparatus of claim 1 ,
wherein the at least one wire winding is configured as a Z-gradient coil,
wherein the at least one solid cross-section wire comprises a cross-sectional area less than that of the at least one hollow cross-section wire, and
wherein one of: each at least one solid cross-section wire is disposed in one of adjacent and proximate two hollow cross-section wires, and two solid cross-section wires are disposed in one of adjacent and proximate each at least one hollow cross-section wire.

7. The apparatus of claim 1 , further comprising an electrically insulating thermally transferring layer disposed in at least one of: between at least a portion of the at least one solid cross-section wire and at least a portion of the at least one hollow cross-section wire, on at least a portion of the at least one solid cross-section wire, and on at least a portion of the at least one hollow cross-section wire,
wherein the electrically insulating thermally transferring layer facilitates electrical separation between the at least one hollow wire and the at least one solid cross-section wire,
wherein the electrically insulating thermally transferring layer facilities heat transfer, and
wherein the electrically insulating thermally transferring layer comprises at least one of a polyimide film, an enamel coating, a thermally conductive enamel coating, an epoxy layer, a thermally conductive epoxy layer, and any other suitable electrically insulating material,
whereby heat transfer for cooling apparatus is facilitated.

8. A method of fabricating a coil apparatus for magnetic resonance imaging, comprising:
providing at least one wire winding,
providing the at least one wire winding comprising providing at least one hollow cross-section wire and at least one solid cross-section wire,
providing the at least one solid cross-section wire disposed adjacent and proximate to the at least one hollow cross-section wire,
providing the at least one solid cross-section wire directed parallel to the at least one hollow cross-section wire along the path of the at least one wire winding,
providing the at least one wire winding configured to carry electrical current such that each of the at least one solid cross-section wire and each of the at least one hollow cross-section wire are electrically connected in series with each other and convey simultaneously the same electrical current,
providing an electrical power supply configured to drive electrical current through the at least one wire winding,
providing a liquid cooling source configured to flow liquid coolant through the at least one hollow cross-section wire continuously, and
whereby at least one of current density, winding density, and heat extraction are increasable,
wherein the at least one hollow cross-section wire comprises a plurality of hollow cross-section wires,
wherein the plurality of hollow cross-section wires comprises a set of hollow cross-section wires,
wherein each hollow cross-section wire of the set comprises a plurality of parallel manifolds for increasing total coolant flow rate, for a given pressure drop across the set, wherein heat extraction is increasable,
wherein the plurality of parallel manifolds facilitates electrical current flow from the set to one of an adjacent set and a proximate set of hollow cross-section wires,
wherein the plurality of parallel manifolds directs coolant flow in relation to a winding segment, and

wherein each parallel manifold of the plurality of parallel manifolds is configured to insert into each at least one hollow cross-section wire via a through-hole and to effect parallel coolant flow paths to reduce overall flow resistance and to improve cooling.

9. The method of claim 8 , wherein at least one of:
providing the at least one solid cross-section wire comprises providing at least one solid small cross-section wire and at least one solid large cross-section wire,
providing the at least one solid large cross-section wire comprises providing a cross-section area greater than that of the at least one solid small cross-section wire,
providi

Assignees

• Synaptive Medical Inc

Inventors

• Bindseil Geron André
• Connell Ian Robert Oliphant
• Handler William Bradfield
• Harris Chad Tyler

Classifications

• G01R33/3856 Primary

  Means for cooling the gradient coils or thermal shielding of the gradient coils · CPC title

• G01R33/3858

  Manufacture and installation of gradient coils, means for providing mechanical support to parts of the gradient-coil assembly (manufacture of inductances or coils in general H01F41/00) · CPC title

• G01R33/3802

  Manufacture or installation of magnet assemblies; Additional hardware for transportation or installation of the magnet assembly or for providing mechanical support to components of the magnet assembly · CPC title

• G01R33/283

  Intercom or optical viewing arrangements, structurally associated with NMR apparatus · CPC title