{HEAD ~ The other end} of the oscillating arm 24 is formed with {TAIL ~ a plurality} of internal threads 241 adapted to engage with a gear 25 fixedly mounted on an output shaft of a motor 20 
is formed with
{ HEAD ~ The other end } of the oscillating arm 24 is formed with { TAIL ~ a plurality } of internal threads 241 adapted to engage with a gear 25 fixedly mounted on an output shaft of a motor 20
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH