{HEAD ~ Vertical movement} of the plunger actuates {TAIL ~ a cam} or screw to vary the setting of the control element of the level control system 
{ HEAD ~ Vertical movement } of the plunger actuates { TAIL ~ a cam } or screw to vary the setting of the control element of the level control system
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH