a control device for enabling {HEAD ~ the apparatus} to displace in {TAIL ~ an automatic way} from a rest position to the checking condition, and vice versa 
to displace in
a control device for enabling { HEAD ~ the apparatus } to displace in { TAIL ~ an automatic way } from a rest position to the checking condition , and vice versa
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH