Toroidal coil device

Purpose: To decrease heat generation due to induced current of a toroidal coil while maintaining its mechanical strength by specifying the structure of the support member for centralizing stress. Constitution: A ring as a centralizing stress support for toroidal coil is formed from a band-like metal member such as stainless steel having such a sufficient mechanical strength and a thickness that heat generation produced by induced current may not form a great thermal load to the cooling system for the super conductive coils by winding the same into a coil-like configuration intervening an insulation material and impregnating entirely with an epoxy resin or the like. Since no circulating current is induced when the ring is disposed in the space inside of the coil and the metal member is made thin, no heat generation due to eddy current occurs therein. (Horiuchi, T.)