Method for operating a servo motor driven turning station of a stacking tool for a punch press

A method for operating a servo motor driven turning station of a stacking tool for a punch press, comprising the steps of:

• a) determining a target rotational acceleration curve of the turning station in the acceleration phase (A) of the turning increment (D);
• b) carrying out a reference acceleration run of the turning station while providing a certain reference drive torque by the servo motor or while supplying the servo motor with a certain reference supply current;
• c) determining one or more of the following reference parameters of the reference acceleration run:
• c1) the reference turning acceleration of the turning station or of the servo motor achieved over a certain turning range;
• c2) the reference angular velocity (ωref) of the turning station or of the servo motor when a certain turning angle is reached;
• c3) the reference turning time (tref) elapsed until a certain turning angle is reached;
• c4) the reference turning angle after a certain turning time has elapsed;
• d) determining one or more of the following target parameters from the target turning acceleration curve:
• d1) the target turning acceleration, which is to be present in a certain turning range;
• d2) the target angular velocity (ωsoll), which should be present when a certain turning angle is reached;
• d3) the target turning time (tsoll) which is to be present when a certain turning angle is reached;
• d4) the target turning angle, which should be present when a certain turning time is reached;
• e) calculating a target drive torque and/or a target supply current of the servo motor, at which the target turning acceleration, the target angular velocity (ωsoll), the target turning time (tsoll) and/or the target turning angle results, from the relationship, known from the reference acceleration run, between the reference turning acceleration, the reference angular velocity (ωref), the reference turning time (tref) and/or the reference turning angle and the drive torque of the servo motor and/or the supply current of the servo motor;
• and thereafter
• f) accelerating the turning station with the servo motor in normal production operation in the acceleration phase (A) of the turning increment (D) while providing the target drive torque by the servo motor or while supplying the servo motor with the target supply current.