The operation principle of tension zone differentiation of film sprocket

1. the tension area

The tension area of a gravure press can be divided into three areas: the uncoiling tension area, the printing tension area and the sashing tension area. The uncoiling tension area comprises the tension control between the web core shaft and the feeding tension roller in the guide group; The printing tension area comprises the tension control between the feeding tension roller in the guide group and the discharging paper tension roller in the printing group; The slitting tension area is between the paper roll of the printing group and the slitting tension roll. For gravure presses with no slitting set and only rewinding set, the slitting tension area includes the area between the paper tension roll and the rewinding roll.

2. Control principle of tension area

The tension control of the uncoiling tension area of the film splitter is mainly completed by the uncoiling machine. Tension control is one of the main functions of the uncoiler, so the control principle of the tension area is the same as the operating principle of the uncoiler. The closed loop control system is composed of clutch, tension roller and tension controller.

The printing tension area is an important link in the tension control system of gravure printing machine, and it is the key to ensure the precision of printing registration. The tension control in the tension area adopts the differential principle. The system adjusts the tension of paper by controlling the working speed of the tension roller and the tension roller. At present, most gravure presses have feed tension rolls that are synchronized with the speed of the press, and the end of the feed tension roll is connected to a stepping motor to achieve differential control.

The tension control in the tension area of the film slitter machine is also very important. If the tension is not stable and the cutting accuracy is not reached, the waste will be produced. For this reason, the tension area is generally selected with the same control method of printing tension area. Its basic speed is the working speed of the printing group and the paper tension roller. The shaft end of the paper roller in the scuttling group is connected with the stepping motor to complete the differential control.