magnetic pole detecting means disposed in {HEAD ~ an internal space} of {TAIL ~ the housing member} for detecting the position of a magnetic pole on the permanent magnet member 
of
magnetic pole detecting means disposed in { HEAD ~ an internal space } of { TAIL ~ the housing member } for detecting the position of a magnetic pole on the permanent magnet member
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH