Patent GB-1160949-A (GB)
Title: Superconductor Coils
IPC: H01F6/06
Filed: 1968-08-14
Abstract: 1,160,949. Superconductor coils. SIEMENS A.G. 14 Aug., 1968 [17 Aug., 1967], No. 38946/68. Heading H1P. A superconductor coil comprises a winding of a tape form composite conductor having insulation between the successive turns, in which the composite conductor comprises an armouring layer of high tesile strength sandwiched between two stabilized superconductor current carrier layers and having cooling channels defined within the winding for conducting coolant over at least one face of each of the stabilized current-carrier layers. As shown. Fig. 1, the composite conductor 1 comprises a non-magnetic stainless steel tape 6 sandwiched between two stabilized current carriers 3, 4, each of which comprises a tape of normal metal in which is embedded a plurality of wires of superconductor material. Both faces of each of the current carriers 3, 4 are provided with transverse grooves 8 and the composite conductor is wound on to a former 2 together with an insulating tape 7. The components of the composite conductor need not be mechanically secured together, and the current carriers 3, 4 are connected in parallel. The following alternative constructions are described: (i) The grooves are formed on the outer faces of the current carriers (1], 12) and an insulating tape (15) is wrapped round the composite conductor with spaced helical turns, Fig. 2 (not shown). (ii) The grooves are formed in the insulating tape inserted between the turns of the composite conductor instead of in the faces of the current carriers, Fig. 3 (not shown). (iii) The armouring layer (32) has a plurality of longitudinally extending ridges (33) on both faces, the current carriers comprise parallel stabilized conductors (30) each located between adjacent ridges, the outer faces of the stabilized conductors have transverse grooves (36) and the whole is wrapped with spaced helical turns of a tape (34) comprising insulating material with a copper underlayer (35) which connects the stabilized conductors in parallel, Fig. 4 (not shown). The ridges (33) may be omitted. (iv) The composite conductor of (iii) is wrapped with spaced helical turns of copper tape (37) in one direction and insulating tape (38) in the opposite direction, Fig. 5 (not shown). The insulating tape may be parallel to the length instead of being wrapped. (v) The armouring layer is sandwiched between copper tapes to which copper wires are soldered to form ridges, the remainder of the construction being similar to (iii) but the copper underlayer of the insulating tape is omitted, Fig. 6 (not shown). (vi) The armouring layer (51) is sandwiched between copper foils (52) and the current carriers comprises a plurality of stranded cables (50) of stabilized superconductor material, and the whole is wound with spaced helical turns of insulating tape (53) which may be formed with grooves, Fig. 7 (not shown). The foils on the armouring layer may be replaced by a copper underlayer on the wrapping tape. (vii) The armouring layer (51) is wound with spaced helical turns of copper tape (54) and the current carriers comprise a plurality of stranded cables (50), Fig. 8 (not shown). This construction may be applied to any of the other constructions except (vi). The armouring may be steel or glass fibre tape, the insulating material may be of plastics reinforced with glass fibre or of glass fibre impregnated with epoxy resin and the stabilized current carriers may be of copper or aluminium containing superconductor wires of niobiumzirconium or niobium-titanium.