Patent ID: 7263839

Claim:
A cooling device for cooling a superconducting coil assembly in an MR apparatus, comprising: a cooling chamber adapted to contain a cooling agent which is in thermal contact with the superconducting coil assembly, a refrigerator for cooling the cooling agent, and a cooling agent storage in fluid connection with the cooling chamber, the cooling agent storage being adapted to take up cooling agent from the cooling chamber when at least a part of the cooling agent in the cooling chamber exceeds a first predetermined temperature, and to return cooling agent to the cooling chamber when at least a part of the cooling agent in the cooling chamber remains below or is equal to a second predetermined temperature, the cooling agent storage including a pressure tank in fluid connection with the cooling chamber for taking up the compressed cooling agent and a compressor means interposed in a fluid connection between the cooling chamber and the pressure tank in order to compress the cooling agent exiting the cooling chamber.