{TAIL ~ a means} for comparison that compares a load detection value obtained based upon detection signals from said load sensors with {HEAD ~ a predetermined overload value} 
{ TAIL ~ a means } for comparison that compares a load detection value obtained based upon detection signals from said load sensors with { HEAD ~ a predetermined overload value }
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD