CRYOSTAT EQUIPPED WITH REFRIGERATOR

PURPOSE:To reduce a noise by a method wherein an expander of a cryostat loaded with a refrigerator causing a vibration and a vacuum container are united elastically by using a bellows and an own weight of the expander and a vacuum pressure load are supported rigidly by using a magnetic shielding body which is installed at the outside of the cryostat and whose mass is large so that a vibration of the expander can be absorbed by the magnetic shielding body. CONSTITUTION:A vibration of an expander 10 used to cool liquid helium tanks 5 storing superconducting magnets 2 is absorbed by a magnetic shielding body 17 whose mass is 100 times or higher that of the expander via a flange 18; it is not propagated to vacuum containers 7 connected by a bellows 19 of an elastic support body. ln addition, a noise produced by the expander itself is absorbed inside a sound-insulating cover 20 surrounding a head part of the expander including pipes 11, 12.