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