Processing apparatus

A processing apparatus comprising:

• a holding table for holding a workpiece;
• a spindle adapted to be rotated;
• a cutting blade mounted on the spindle, the cutting blade having a cutting edge for cutting the workpiece held on the holding table;
• measuring means for measuring an edge projection amount of the cutting edge at a predetermined frequency;
• and
• a data processing portion, wherein
• the data processing portion includes:
• a lower limit recording portion for recording a lower limit of the edge projection amount of the cutting edge as an allowable limit for use of the cutting blade,
• a storing portion for storing blade information including the edge projection amount measured by the measuring means and a cutting distance traveled by the cutting blade at the time of measurement of the edge projection amount, the edge projection amount and the cutting distance being stored in a one-to-one correspondence manner,
• an inclination calculating portion for calculating an inclination such that the edge projection amount decreases with an increase in the cutting distance, from a plurality of pieces of the blade information stored in the storing portion by performing two or more measurements using the measuring means, and
• a predicting portion for calculating a maximum cutting distance corresponding to the lower limit of the edge projection amount from the inclination calculated by the inclination calculating portion.