PURPOSE: To prevent deterioration, caused by heat, of an arrow feather type heat insulating support member by a method wherein said support is attached to an intermediate heat shielding board surrounding an inner vessel and the end of one of said feather type member is fixed to an inner vessel side support seat and the end of the other is inserted into an outer vessel inside wall slidably, when a liquid He reservoir inner vessel is installed on the inside wall of a vacuum containing outer vessel.

CONSTITUTION: This relates to a method of attaching an inner vessel 7 to a vacuum containing outer vessel 5 in a liquid He reservoir 7 used aboard a vehicle levitated by magnetism generated by a superconductor or the like. An arrow feather shaped support 6 made of heat insulating material is attached to an intermediate heat shielding board 22, enclosing the inner container 7, in contact with the outer vessel 5 at a right angle. And a support ring 18C with its periphery abutting against the outer vessel 5 is provided on the outside of the support 6. The feather type member 14A is fixed to a support seat 15 provided at an end of the inner vessel 7 and the feather 14B is fixed to an outer vessel side support seat 19 of the support ring 18C. Thus constructed, with the ring 18C not welded to the outer vessel 5 and therefore slidable, the inner vessel 7 is capable of travelling a short distance.