{HEAD ~ a discharge part} that discharges {TAIL ~ the gas} sucked by the suction part, the discharge part having a plurality of rotating impellers and a stationary impeller arranged so as to be opposed to each of the plurality of rotating impellers; and 
discharges
{ HEAD ~ a discharge part } that discharges { TAIL ~ the gas } sucked by the suction part , the discharge part having a plurality of rotating impellers and a stationary impeller arranged so as to be opposed to each of the plurality of rotating impellers ; and
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH