For an arrangement of the elastic elements substantially radially outside of the impeller wheel, {HEAD ~ the first driving device} extends beyond {TAIL ~ this impeller wheel} 
extends beyond
For an arrangement of the elastic elements substantially radially outside of the impeller wheel , { HEAD ~ the first driving device } extends beyond { TAIL ~ this impeller wheel }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL