What is the control principle of an intaglio printing press?

Tension Zone Division
The tension zones of an intaglio press can be divided into three zones: unwinding tension zone, printing tension zone, and slitting tension zone. The unwinding tension zone includes the tension control between the paper core shaft of the roll and the paper feed tension roller in the guide group; the printing tension zone includes the tension control between the paper feed tension roller in the guide group and the paper delivery tension roller in the printing group; the area between the paper delivery roller in the printing group and the slitting tension roller is the slitting tension zone. For intaglio presses without a slitting group but only a rewinding group, the slitting tension zone includes the area between the paper tension roller and the rewinding shaft.
Control Principle
The tension control in the unwinding tension zone is mainly completed by the unwinder. Tension control is a major function of the unwinder, so the control principle of this tension zone is consistent with the working principle of the unwinder, consisting of a clutch, tension roller, and tension controller to form a closed-loop control system.
The printing tension zone is an important part of the intaglio press tension control system and is the key to ensuring accurate printing register. The tension control in this tension zone adopts the differential speed principle. The system adjusts the paper tension by controlling the rotational speed of the paper feed tension roller and the paper delivery tension roller. The paper feed tension roller of most intaglio presses is synchronized with the printing machine speed, and the shaft end of the paper delivery tension roller is connected to a stepper motor to achieve differential speed control.
The tension control in the slitting tension zone is also very important. If the slitting accuracy cannot be achieved due to unstable tension, defective products will be produced. Therefore, this tension zone generally adopts the same control method as the printing tension zone. Its basic speed is the rotational speed of the paper tension roller of the printing group, and the shaft end of the paper delivery roller of the slitting group is connected to a stepper motor to achieve differential speed control.