The detector includes a microswitch having a sensing arm which contacts {HEAD ~ a center portion} of {TAIL ~ an elastic membrane} 
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The detector includes a microswitch having a sensing arm which contacts { HEAD ~ a center portion } of { TAIL ~ an elastic membrane }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL