| 摘要 |
A bearing assembly 9 comprises an inner race 11, an outer race 10, a plurality of balls 12 sandwiched therebetween, and a single seal 13 comprising an annular rubber skin 14, the single seal being fixed to one of the inner or outer races and extending towards and into abutment with the other of the races. The seal may be supplemented by a rigid annular cover 15 (fig.3) which does not come into contact with the inner race. The use of a single seal reduces the friction of prior art bearings having a pair seals. Also disclosed is a rotor assembly comprising a rotor shaft 8 mounted by means of two bearing assemblies 9 in the central column 3 of a stator assembly. The central column 3 and the bearing assemblies 9 define an enclosure having a pair of seals 13, each seal being adjacent a bearing assembly, outside the enclosure, and extending from the stator assembly 3 or the outer race 10 to the rotor shaft 8 or the inner race 11. The arrangement allows an entirely unsealed bearing assembly 9 to operate in an entirely sealed environment. |
