In {TAIL ~ this case}, {HEAD ~ a magnet A} having a portion B which does not change the breadth of a magnet in the circumferential direction even if the distance from the center of revolution changes, is arranged 
In
In { TAIL ~ this case } , { HEAD ~ a magnet A } having a portion B which does not change the breadth of a magnet in the circumferential direction even if the distance from the center of revolution changes , is arranged
REL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH