Gradient coil and gradient coil unit for MRI and methods of manufacturing the same

A method of manufacturing a gradient coil for magnetic resonance imaging., in which the gradient coil consists of at least one of the x-coil and y-coil among an x-coil, a y-coil and a z-coil wound on predetermined positions of a nonmagnetic hollow cylindrical bobbin, said method comprising:

• a preparatory step of preparing a conductor plate;
• a stamping step of stamping a plurality of gradient coil pieces having a predetermined pattern out of the prepared conductor plate;
• a forming step of curving the stamped gradient coil pieces in conformity with a curvature of an outer circumferential surface of the bobbin;
• and
• a lamination step of superposing the curved gradient coil pieces one on another.

A method of manufacturing a gradient coil for magnetic resonance imaging, in which the gradient coil consists of at least one of the x-coil and y-coil among an x-coil, a y-coil and a z-coil wound on predetermined positions of a nonmagnetic hollow cylindrical bobbin, said method comprising:

• a preparatory step of preparing a conductor plate and an insulating adherent sheet;
• a stamping step of stamping a plurality of gradient coil pieces having a predetermined pattern out of the prepared conductor plate the gradient coil pieces forming the gradient coil;
• a forming step of curving the stamped gradient coil pieces in conformity with a curvature of an outer circumferential surface of the bobbin;
• and
• a lamination step of superposing the curved gradient coil pieces one on another while interposing the prepared insulating adherent sheet therebetween.

A method of manufacturing a gradient coil unit for magnetic resonance imaging in which x-coils, y-coils and z-coils are as the gradient coil wound on predetermined positions of a nonmagnetic hollow cylindrical bobbin, said method comprising:

• a first process for manufacturing the x- and y-coils, said first process including a first preparatory step of preparing a conductor plate and a plurality of insulating adherent sheets, a second preparatory step of preparing two bobbins having different diameters, a stamping step of stamping a plurality of x-coil pieces and a plurality of y-coil pieces each having a predetermined pattern out of the prepared conductor plate, the x-coil pieces and the y-coil pieces each forming the x-coil and the y-coil, a forming step of curving each of groups of the stamped x- and y-coil pieces in conformity with curvatures of outer circumferential surfaces of the two bobbins, and a lamination step of superposing individually each of the groups of x- and y-coils as said x- and y-coils while interposing one of the prepared insulating adherent sheets therebetween;
• a second process of laminating the x- and y-coils and said z-coils at predetermined positions on the two bobbins each while interposing another one of the insulating adherent sheets therebetween after said first process;
• and
• a third process including a step of preparing a nonmagnetic spacer and a step of fitting the two bobbins one in another with said spacer interposed therebetween after said second process.