{HEAD ~ The force transmission or transport device} 7, wherein the friction clutch comprises {TAIL ~ a pair} of friction wheels  
{ HEAD ~ The force transmission or transport device } 7 , wherein the friction clutch comprises { TAIL ~ a pair } of friction wheels
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH