| 摘要 |
A cryostat has a cooling arm with a first thermal contact surface which can be brought into thermal contact with a second thermal contact surface on an object to be cooled. A hollow volume (2) between the inner side of the neck tube, the cooling arm, and the object is filled with gas and the cooling arm is pressurized by the inner pressure of the gas and also by atmospheric pressure. A contact device brings the first and the second contact surfaces into thermal contact below a threshold gas pressure and moves them away from each other when the threshold pressure has been exceeded such that a gap (13) filled with gas thermally separates the first and second contact surfaces. Operationally safe and fully automatic reduction of the thermal load acting on the object to be cooled is thereby obtained in case the cooling machine fails. |
