[en] Purpose: To decrease the size of supports for large toroidal coils. Constitution: A plurality of (24) toroidal coils whose respective taper-like opposing surfaces are fabricated precisely are closely contacted to each other along the entire surface for the taper-like opposing surfaces and disposed in the toroidal direction and clamped by way of plate insulator to a ring. This provides the taper-like opposing surfaces of the toroidal coils with an edge effect causing image current to flow in the toroidal and the poloidal directions. The image current provides shell effect against plasmas, whereby the provision of the shells are saved and the magnetic force supporting function of the rack for supporting the toroidal coils can be reduced. (Ikeda, J.)