The eccentric discs 213 and the cranks 223 are all mounted with their lines of throw, in parallel and {HEAD ~ parallelism} is maintained as {TAIL ~ the cranks} 223 and eccentric discs 213 rotate 
is maintained as
The eccentric discs 213 and the cranks 223 are all mounted with their lines of throw , in parallel and { HEAD ~ parallelism } is maintained as { TAIL ~ the cranks } 223 and eccentric discs 213 rotate
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 REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH