Patent ID: 7464556

Claim:
A magnetic resonance apparatus comprising: a cryostat; a superconducting magnet coil disposed in said cryostat; and a refrigerator for cooling at least one of said cryostat and said magnet coil, said refrigerator having a compressor for compressing a working gas, a cold head, a control valve, a high pressure line disposed between said compressor and said control valve, a low pressure line disposed between said compressor and said control valve, and at least one connecting line disposed between said control valve and said cold head, wherein said control valve periodically connects said high pressure line and said low pressure line to said connecting line to produce pressure pulses through the working gas, wherein said control valve is rigidly mechanically coupled to said cryostat and at least one of said high pressure line and said low pressure line is branched on a compressor side upstream of said control valve and is symmetrically joined at said control valve such that pressure pulses through the working gas are vectorially compensated for at said control valve to minimize vibrations of said cryostat.