Method and device for operating a drawing line or drawing unit

A method for driving a drawing line or drawing unit for drawing of tows having polymer filaments comprising a plurality of driven drawing rollers for drawing the tows and a plurality of separately controllable drive units, one of the plurality of separately controllable drive units being operably connected to each of the driven drawing rollers for individually controlling the torque on each drawing roller, said method comprising:

• comparing a measured torque on a given drawing roller of the plurality of drawing rollers to a setpoint torque for the given drawing roller;
• and
• controlling the drive unit controlling the given drawing roller to bring the measured torque closer to the setpoint torque,
• wherein said individually controlling the torque on each drawing roller is done automatically through gradual approximation based on a setpoint torque curve or a setpoint torque characteristic,
• wherein each drawing roller is controlled to run at a specified rotational speed based on a current control,
• wherein said individually controlling the torque is continued until the torque on each drawing roller meets the setpoint torque and each drawing roller reaches the specified rotational speed, and
• wherein torques of the separately controllable drive units are controlled until a same torque is given throughout.

A method for driving a drawing line or drawing unit for drawing of tows having polymer filaments comprising a plurality of driven drawing rollers for drawing the tows and a plurality of separately controllable drive units, one of the plurality of separately controllable drive units being operably connected to each of the driven drawing rollers for individually controlling a torque on each drawing roller, said method comprising:

• comparing a measured torque on a given drawing roller to a setpoint torque for the given drawing roller;
• and
• controlling the drive unit operably connected to the given drawing roller so that the measured torque on the given drawing roller of the plurality of drawing rollers approaches the setpoint torque for the given drawing roller,
• wherein said individually controlling the torque on each drawing roller is done automatically through gradual approximation based on a setpoint torque curve or a setpoint torque characteristic and wherein said individually controlling the torque is continued until the torque on each drawing roller meets the setpoint torque, and
• wherein torques of the separately controllable drive units are controlled until a same torque is given throughout.