Servomechanism for rotary type flying cutting apparatus

A servomechanism for rotary type flying cutting apparatus comprising:

• a cutter rotating into contact with a member moving in a straight line in a predetermined range of rotation of the cutter for cutting the member;
• a servomotor for driving the cutter;
• a length measuring pulse generator for generating length measuring pulses corresponding in number to the distance of movement of the moving member;
• a rotation measuring pulse generator for generating rotation measuring pulses corresponding in number to the rotation of the cutter;
• subtracting means for obtaining the difference between the number of the length measuring pulses derived from the length measuring pulse generator and the number of the rotation measuring pulses derived from the rotation measuring pulse generator;
• a setting device for setting therein a set length corresponding to a desired cutting length of the moving member;
• a digital subtractor for detecting the set length and the result of subtraction by the subtracting means;
• a D-A converter for converting the result of subtraction by the digital subtractor and supplying it as a control signal to the servomotor;
• a memory for storing therein a corrected value corresponding to the component of unit distance of movement of the cutter in the direction of travel of the moving member with respect to each angular position of the cutter in the predetermined range of rotation of the cutter;
• address signal generating means for generating an address signal for reading out the memory in accordance with the rotational angular position of the cutter in the predetermined range of rotation of the cutter;
• and
• means for correcting the difference between the number of the rotation measuring pulses and the number of the length measuring pulses by the corrected value read out from the memory so that the distance of movement of the moving member and the component of the movement of the cutter in the direction of travel of the moving member may be equal to each other in the predetermined range of rotation of the cutter.