Cryogenic magnet systems

Patent · Tue Jul 21 00:00:00 EDT 1987

OSTI ID:6032791

Sarwinski, R E; Purcell, J R; Parker, J W; Burnett, S C

This patent describes a cryogenic superconducting magnet system for use in magnetic resonance imaging (MRI) devices, the system comprising: an evacuated container, a first tank mounted within the evacuated container and thermally insulated; boiling liquid helium disposed in the first tank and exhausted to the outside of the container; a cryogenic superconducting magnet disposed in the first tank, a metallic heat radiation shield disposed in the evacuated container and substantially surrounding the first tank, the shield being thermally insulated from both the container and the first tank; and a neon refrigeration system external to the shield for cooling the shield, the neon refrigeration system including neon refrigerant. A second tank contains the neon refrigerant in its liquid state, at least one thermal siphon for circulating the neon refrigerant by convection from the second tank to the shield. The boiling of the neon refrigerant at the shield acts to circulate the neon refrigerant in the thermal siphon and cool the shield. A mechanical cryoccooler is remote from the container for condensing the neon refrigerant from the gaseous to the liquid state, and thermally insulated transfer means for transferring the neon refrigerant in its gaseous state from the second tank to the cryocooler. The neon refrigerant is in its liquid state from the cryocooler to the second tank.

• Assignee: GA Technologies Inc., San Diego, CA
• Patent Number(s): US 4680936
• OSTI ID: 6032791
• Resource Relation: Patent File Date: Filed date 24 Dec 1985
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
SUPERCONDUCTING MAGNETS
CRYOGENICS
DESIGN
OPERATION
BOILING
CONTAINERS
CONVECTION
HELIUM
LIQUEFIED GASES
MAGNETIC RESONANCE
NEON
REFRIGERANTS
REFRIGERATING MACHINERY
TANKS
THERMAL INSULATION
THERMAL SHIELDS
ELECTRICAL EQUIPMENT
ELECTROMAGNETS
ELEMENTS
ENERGY TRANSFER
EQUIPMENT
FLUIDS
GASES
HEAT TRANSFER
MACHINERY
MAGNETS
MASS TRANSFER
NONMETALS
PHASE TRANSFORMATIONS
RARE GASES
RESONANCE
SHIELDS
SUPERCONDUCTING DEVICES
WORKING FLUIDS
420201* - Engineering- Cryogenic Equipment & Devices