| 摘要 |
928,052. Handling radio-active material. COMMISSARIAT A L'ENERGIE ATOMIQUE. June 29, 1960 [July 7, 1959; April 22, 1960], No. 22800/60. Class 39 (4). [Also in Group XXV] An arm 2 forming part of a remote-control device and pivoted in an orifice in a protective wall 42 passes diametrically through a sphere 1 of radiation absorbent material, e.g. lead, at least partly encased by hard material e.g. steel, and provided with at least one raceway in the surface of the casing, the sphere being rotatable on ball or roller bearings about an axis perpendicular to the axis of the raceway and passing through the centre of the sphere, and the bearings being carried by a part which is itself rotatable in the orifice about an axis perpendicular to the first axis and passing through the centre of the sphere. As shown in Figs. 3 and 4, the hard casing 28 comprises a ring having a single roller race 29 engaged by two rollers 30, 31 (Fig. 7) carried by a part 11 pivoted about a vertical axis 39. The part 11 carries two further rollers 32, 33 which engage the ring 28 on each side of the raceway 29 and are either pivoted on inclined axes, as shown, or pivoted on horizontal axes and formed with conical peripheral surfaces. The orifice has an internally threaded lining 40 of bronze or other material and the sphere 1 is located in the orifice by housing shells 44, 45 of lead surrounded by hard metal linings 46 which screw into the lining 40. A bellows 54 is fixed between one end of the arm 2 and the rim 53 of an orifice 52 in an inner sealing wall 51 to prevent the escape of contamination from the space enclosed by the walls 42 and 51. In an alternative embodiment the sphere 1 of lead is encased by shells of hardened steel formed with two parallel races 5, 6 (Fig. 9) engaged by suitably disposed bearings on the part 11, and the housing shells are permanently secured to the protective wall. These bearings may be of cylindrical or conical form, the races 5, 6 being of corresponding shape. |
