Having the winding bobbin (8) superconducting wire (6) of the winding portions wound in layers (5), a metal plate provided between the forming layer between the superconducting wire (6) and (9), a metal plate (9), between the superconducting wire adjacent to each other in the same layer in (6), the convex portion as taken along the superconducting wire (6) (9 b) are provided. Winding bobbins (8) comprises a cylindrical portion and (8a), a pair of flanges (8 b, 8c) which the cylindrical portion provided at both ends in the axial direction (8a) is thermally connected to the cylindrical portion (8a) and, the metal plate (9) includes a contact region in contact with superconducting wire (. 6) (9a), extending from the contact region (9a) to the flange (8 b), the circumferential direction of the width of the contact area of the cylindrical portion (8a) (9a ) and a circumferential width than the narrow lead-out area (9c) of. Lead region (9c) penetrates the flange (8 b), it reaches the freezer (3) and the flange (8 b) and the cooling head thermally connects (10). This provides a superconducting coil (2) which can suppress an increase in temperature gradients generated in the winding portion (5).巻ボビン(8)に超電導線(6)が層状に巻回された巻線部(5)と、超電導線(6)のなす層同士の間に設けられる金属板(9)とを有し、金属板(9)には、同一の層内で互いに隣り合う超電導線(6)の間に、超電導線(6)に沿うような凸部(9b)が設けられる。巻ボビン(8)は、円筒部(8a)と、円筒部(8a)の軸方向の両端に設けられ円筒部(8a)と熱的に接続する一対のフランジ(8b、8c)とを備え、金属板(9)は、超電導線(6)に接触する接触領域(9a)と、接触領域(9a)からフランジ(8b)へ伸び、円筒部(8a)の周方向の幅が接触領域(9a)の周方向の幅より狭い引出領域(9c)とを備える。引出領域(9c)は、フランジ(8b)を貫通し、冷凍機(3)とフランジ(8b)とに熱的に接続する冷却ヘッド(10)に達する。これにより、巻線部(5)内に生じる温度勾配の増大を抑制できる超電導コイル(2)を提供する。
