When {HEAD ~ the upper surface} of {TAIL ~ the workpiece} is detected, a plate thickness calculation section calculates a plate thickness of the workpiece based on an upper surface position of a die, that is known in advance and stored in a memory 
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When { HEAD ~ the upper surface } of { TAIL ~ the workpiece } is detected , a plate thickness calculation section calculates a plate thickness of the workpiece based on an upper surface position of a die , that is known in advance and stored in a memory
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL 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