When {TAIL ~ the upper surface} of the workpiece is detected, {HEAD ~ 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 
When { TAIL ~ the upper surface } of the workpiece is detected , { HEAD ~ 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 TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD 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