Adjustment method of a magnetic resonance imaging apparatus

Patent metadata

Field	Value
Publication number	US-10073155-B2
Application number	US-201715446597-A
Country	US
Kind code	B2
Filing date	Mar 1, 2017
Priority date	Jun 11, 2009
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

An adjustment method of a magnetic resonance imaging apparatus includes: a cooling and excitation step in which work of transporting a superconducting magnet to a facility different from a facility where the superconducting magnet is to be installed, cooling a superconducting coil of the superconducting magnet with a refrigerant, and supplying a current from an external power supply for excitation is repeated until a predetermined rated current flows; a demagnetization and transportation step of demagnetizing the superconducting coil and transporting the superconducting magnet to the facility where the superconducting magnet is to be installed in a state where the superconducting coil is cooled by the refrigerant; and an installation step of installing the superconducting magnet in the facility where the superconducting magnet is to be installed and supplying a predetermined rated current from an external power supply to the superconducting coil in order to excite the superconducting coil.

First claim

The invention claimed is:

1. An adjustment method of a magnetic resonance imaging apparatus including a superconducting magnet, comprising:
a cooling and excitation step of temporarily installing the superconducting magnet, which is manufactured in advance and then is transported to a work facility site, at the work site facility and cooling a superconducting coil of the superconducting magnet with a refrigerant, wherein, at the work site facility, supplying a current from an external power supply for excitation to the superconducting coil is executed until a predetermined rated current flows; and
a demagnetization and transportation step of demagnetizing the superconducting coil excited by the rated current as a preliminary step and transporting the superconducting magnet from the work site facility in a state where the superconducting coil is cooled by the refrigerant.

2. The adjustment method according to claim 1 ,
wherein a plant for condensing helium gas to liquid helium, a frame on which the superconducting magnet is mounted, a supply pipe used to send liquid helium from the plant to the superconducting magnet, and a recovery pipe used to send helium gas from the superconducting magnet to the plant are provided in the work site facility for excitation.

3. The adjustment method according to claim 1 ,
wherein in the cooling and excitation step, a current value is increased with a predetermined increase rate when supplying a current from the external power supply to the superconducting coil, and a refrigerant is injected again and the current value from the external power supply is increased with a predetermined current value increase rate when a quench occurs in the superconducting coil and the refrigerant evaporates.

4. The adjustment method according to claim 1 ,
wherein in the demagnetization and transportation step, the superconducting coil is transported while maintaining the superconducting coil at a liquid helium temperature or less after the demagnetization.

5. The adjustment method according to claim 4 ,
wherein in the demagnetization and transportation step, the superconducting coil is stored for a predetermined number of days while maintaining the superconducting coil at the liquid helium temperature or less after the demagnetization.

6. The adjustment method according to claim 5 ,
wherein in the demagnetization and transportation step, at least one of an operation of a cryocooler of the superconducting magnet and refrigerant supplementation is executed during the storage.

Assignees

• Hitachi Ltd

Inventors

• Tsuda Munetaka

Classifications

• A61B5/055 Primary

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• H01F6/04

  Cooling · CPC title

• H01F6/02

  Quenching; Protection arrangements during quenching {(protection circuits H02H7/001)} · CPC title

• Y10T29/49004

  including measuring or testing of device or component part · CPC title

• Y10T29/4908

  Acoustic transducer · CPC title