A detection unit for detecting a data row of a press position and a load at the press position; an input/storage unit for storing at least a load value serving as references for determining stop or judge; a calculation unit of the value of the slope of the load for calculating the value of the slope of the load based on the press position and the load at the press position detected; a calculation unit of the value of the slope of the slope of the load for calculating the value of the slope of the slope of the load based on the calculated value of the slope of the load; and a determination unit for comparing the calculated value of the slope of the slope of the load with the values serving as the references to determine stop or judge are provided.