The linkage mechanism allows the door to move between a closed position where the door is placed against the housing and in front of the opening to prevent access therethrough, and an opened position where {HEAD ~ the door} is placed away from {TAIL ~ the opening} to allow access therethrough 
is placed away from
The linkage mechanism allows the door to move between a closed position where the door is placed against the housing and in front of the opening to prevent access therethrough , and an opened position where { HEAD ~ the door } is placed away from { TAIL ~ the opening } to allow access therethrough
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 OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH