| 摘要 |
<p>A cryogenic vessel comprises a liquid helium tank including a substantially flat top wall and which contains therein a cryogen-cooled electrical apparatus. The helium tank is surrounded by a radiation shield provided with a cooling tube through which evaporated helium gas flows and the radiation shield is then surrounded by an outer housing. In order to evenly cool the top wall of the cryogen tank, it is provided with a heat conducting plate, a cooling coil or a plurality of evenly distributed inlets for substantially evenly cooling it.</p> |
