| 摘要 |
The actuator comprises a concentric arrangement of a stator 223 comprising electromagnetic sectors for generating phased electromagnetic fields around the stator, a first cylindrical rotor element 217 comprising permanent magnetic elements magnetised radially, a second cylindrical rotor element 209 having alternating sectors of high and low magnetic permeability, and a third cylindrical element 201 comprising permanent magnetic elements magnetised radially and arranged to be non-rotatable with respect to the two rotary elements. An alternating helical magnet array with separate threads 205.207,219,221 repeats around the inner surface of element 201 and the outer surface of element 217, the helices of element 201 being oppositely inclined to those of element 217. On the internal surface of element 217 the threads are magnetically arranged to form an axial pattern of magnetic stripes 305,307 (Fig 3a,b not shown). Phased magnetisation of the stator causes the first cylindrical element 217 to rotate around the central axis, thereby causing the second cylindrical element 209 to exert a rotational force around the central axis in the manner of magnetic gearing. Applications of the actuator include prosthetic limbs and orthoses, and for service and remotely operated robots. If the rotor 209 is driven the arrangement forms a generator. |
