Therefore, when die cylinder operates for {HEAD ~ the wheels} to move relative to {TAIL ~ the propped block}, the head member can be adjusted in height together with the connecting block 
to move relative to
Therefore , when die cylinder operates for { HEAD ~ the wheels } to move relative to { TAIL ~ the propped block } , the head member can be adjusted in height together with the connecting block
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH