The control valve 8, wherein said {HEAD ~ valve element} and {TAIL ~ valve seat form} said atmosphere valve 
The control valve 8 , wherein said { HEAD ~ valve element } and { TAIL ~ valve seat form } said atmosphere valve
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH