PURPOSE: To reduce the number of welded joints and to eliminate interference heat between a rotary shaft of a liquid refrigerant supply and exhaust equipment and a refrigerant carrier pipe by linearly connecting the refrigerant carrier pipe, with one end so inserted into a sealing flange and a multiple pipe that gas may not leak in the sealing flange and the multiple pipe and the other end connected to a low- temperature refrigerant storage container located at a fixed place, to the liquid refrigerant supply and exhaust equipment.

CONSTITUTION: One end of a liquid refrigerant carrier pipe is connected to a liquid refrigerant storage container 18 and the other end connected to one end of a multiple pipe 25 of a liquid refrigerant supplying equipment 28 through a gas sealing component 26. A nearly central part of the multiple pipe 25 is supported by the flange fixed at the end of a protective cylinder 15 and the other end of the multiple pipe 25 is inserted to the central hole 8a of a rotary shaft 8 with a certain length of the central hole not in contact with the multiple pipe 25. Since a liquid refrigerant carrier path 29 of the liquid refrigerant supplying equipment 28 located between the liquid refrigerant carrier pipe and a refrigerant supplying equipment is formed linearly, a refrigerant can be carried smoothly. Furthermore, the structure of the pipe is simple and so, the number of welded sections is reduced and eventually the pressure of a vacuum chamber which forms a vacuum heat insulating layer is reduced.