In the piston machine of the present invention, {HEAD ~ the interior} of the crankcase is used as {TAIL ~ a third working chamber} 
is used as
In the piston machine of the present invention , { HEAD ~ the interior } of the crankcase is used as { TAIL ~ a third working chamber }
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL