It is a further object of {HEAD ~ the invention} to provide {TAIL ~ a change gear system} capable of preventing teeth of a rack gear and a pinion to be broken 
to provide
It is a further object of { HEAD ~ the invention } to provide { TAIL ~ a change gear system } capable of preventing teeth of a rack gear and a pinion to be broken
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH