{HEAD ~ Means} for sensing {TAIL ~ an abnormal condition} of the machine tool is provided in the vicinity of an essential portion of the machine tool 
for sensing
{ HEAD ~ Means } for sensing { TAIL ~ an abnormal condition } of the machine tool is provided in the vicinity of an essential portion of the machine tool
HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH