said coupling portion and said main cylindrical member have a pair of holes formed to correspond to each other, one of said pair of holes having {HEAD ~ a tapered surface} inclined with {TAIL ~ respect} to said axial direction, 
said coupling portion and said main cylindrical member have a pair of holes formed to correspond to each other , one of said pair of holes having { HEAD ~ a tapered surface } inclined with { TAIL ~ respect } to said axial direction ,
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 HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH