A diaphragm deflectably spans and sealingly closes the open end of the chamber and urges the pressing roller and thus the sheet material against the driven roller with a force proportionate to {HEAD ~ the pressure} prevailing in {TAIL ~ the chamber} of the housing 
prevailing in
A diaphragm deflectably spans and sealingly closes the open end of the chamber and urges the pressing roller and thus the sheet material against the driven roller with a force proportionate to { HEAD ~ the pressure } prevailing in { TAIL ~ the chamber } of the housing
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 HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH