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