PURPOSE: To detect the end of cutting whereby time required for cutting with a cutter is automatically controlled.

CONSTITUTION: This detection means is composed of a bounce detection means composed of a light emitting element 9 and a light receiving element 10, both of which are disposed in the upper place of a cutter, and an integrating means 12 for integrating the outputs of the light receiving element 10, and a comparison means 14 for comparing the output value of the bounce detection means with a specific value and for outputting a coincidence signal. Further, a cut detection controller for detecting the end of cutting comprises a time measuring means 15 for measuring time from the start of cutting to the input of the coincidence signal from the comparison means 15, and a remaining time arithmetic means 16 which, calculates the the remaining time required for cutting and outputs it based on the time measured by the time measuring means 15.