COOLING STORAGE EXPANDER, PULSE TUBE REFRIGERATING MACHINE, MAGNETIC RESONANCE IMAGING DEVICE, NUCLEAR MAGNETIC RESONATOR, SUPERCONDUCTIVE QUANTUM INTERFERENCE DEVICE FLUXMETER, AND MAGNETIC SHIELDING METHOD OF COOLING STORAGE EXPANDER

摘要

PROBLEM TO BE SOLVED: To provide a cooling storage expander, for shielding, in a cooling storage refrigerating machine provided with a cooling storage expander including a magnetic cooling storage material, magnetic field change by the magnetic cooling storage material without deteriorating the freezing capability of the refrigerating machine. SOLUTION: The cooling storage expander 10 includes cooling storage pipes 1 and 2 storing cold heat in expansion of refrigerant gas; cylinders 3 and 4 connected with the low-temperature end side of the cooling storage pipes 1 and 2 and generating cold heat by repeating compression and expansion of the refrigerant gas through the pipes 1 and 2; a magnetic cooling storage material 23 filled in the inside of the cooling storage pipes 1 and 2, which is formed of a magnetic body and contacts with the refrigerant gas to store the cold heat thereof; and a magnetic shielding member 27 provided to enclose the magnetic cooling storage material 23. The magnetic shielding member 27 includes an electric resistivity at ordinary temperature of 50μΩcm or less. The pulse tube refrigerating machine, the magnetic resonance imaging device, the superconductive quantum interference device fluxmeter, and the magnetic shielding method of the cooling storage expander 10 are also provided. COPYRIGHT: (C)2010,JPO&INPIT