| 摘要 |
PURPOSE:To meet quick temperature change, enhance mechanical reliability and improve operation efficiency by forming a thermal conductive layer consisting of good thermal conductive material is formed to a protruded body in such a way as being placed in contact with it and is connected to a mother body. CONSTITUTION:A thermal conductive layer 8 consisting of copper and aluminium having good thermal conductivity is placed and connected in contact with a helium tank 2 at the surface of protruded reinforcing plate 2a and supporting leg 2b. As a method of placing the thermal conductive layer 8 in contact with the protruded bodies 2a, 2b and helium tank 2, it is just suited to weld a plate by the exprosion welding or to thermally spray copper or aluminium in order to form a layer at the surface. Or, a pair of reinforcing plates 2a, 2a are welded keeping a space and a good thermal conductive material is thermally sprayed to such space and thereby a layer 8 is formed. Thereby, during a preheating before the liquid helium is pored to the helium tank 2 or during temperature rise to the normal temperature after the liquid helium has been pored, heat is transmitted quickly by the thermal conductive layer 8 placed in contact with the protruded body from the helium tank 2. Accordingly, the tank as a whole is almost simultaneously heated to the same temperature. |
