A thermal paper slitting machine is a kind of mechanical equipment to cut the wide thermal paper into several narrow paper rolls. Along with the mechanization degree higher and higher, the request to the winding operation efficiency also higher and higher.

When the user in the paper slitting machine the operation can be the whole volume of the big drum according to different requirements slitting into a number of a small drum, to meet the needs of different occasions. There are many kinds of slitting machines on the market but at the same time there are many defects and shortcomings, such as traditional slitting using the input paper thickness calculation, so the actual diameter error is large, but also need manually real-time monitoring tension control accuracy, when the tension is too loose and tight, need to manually change the parameters.

The tension control system is the core part of the cutting machine. Today we talk about the cutting machine tension control. Tension control is the ability to continuously and steadily control the tension of raw materials as they are transported over the equipment. The tension control of the slitting machine is basically manual tension control and automatic tension control. Manual tension control is to control the tension in the winding or unwinding process, when the coil diameter changes to a certain stage, the operator adjust the manual power supply device, so as to achieve the purpose of controlling the tension.

Automatic tension control is determined directly by the tension sensor of strip tension value, then the tension data into a signal feedback back tension controller, through the signal and the tension controller pre-set value contrast, calculate the control signal, automatic control execution unit, the actual tension values with the preset tension values are equal, in order to achieve the purpose of stable tension.

Tension control must be maintained for any operating speed of the cutting machine, including acceleration, deceleration, and uniform speed.

The ability to ensure that the cut material is not scratched or damaged, even in the event of an emergency shutdown. The stability of tension control is directly related to the quality of cutting products. If the tension is insufficient, the raw materials will become loose or drift during operation, and the finished materials will wrinkle after cutting and rewinding.

If the tension is too large, the raw material is easy to be broken so that the cut and rewinding of the finished product more broken ends. For this reason, constant tension control is required, that is, make the raw material bears the best tension in the winding process, and the tension is always unchanged. There are various tension control schemes available because of the different detection and torque control elements selected.

There are many forms of tension, but the basic principle is the same. The formation of tension is an integral part. In the process of starting, the speed of the rewinding line is greater than that of the rewinding line, so as to generate a certain tension in the rewinding roller. When the rewinding reaches the appropriate tension required by us, the power mechanism should be adjusted timely to stabilize the speed of the rewinding line and the rewinding line. In this way, the raw materials can operate stably under this tension. The tension of the control system is to meet the tension stability of the whole machine.

The factors causing fluctuations and changes in tension are often complex, and the main influencing factors generally include the following aspects:

1. The change in the lifting speed of the machine will inevitably cause a change in the tension of the whole machine.

2. The cutting machine in the winding process, winding and unwinding diameter is constantly changing, the change of diameter will inevitably cause the change of raw material tension. Under the condition of constant braking torque, the unwinding diameter decreases, and the tension increases accordingly. On the contrary, if the winding moment is constant, the tension will decrease with the diameter of the winding increasing. This is the main factor that causes the change of material tension in operation.

3. The change of the tightness of the raw material coil will cause the change of the tension of the whole machine.

4. Non-uniformity of cutting raw materials. For example, the fluctuation of material elasticity, the change of material thickness along the direction of width and length, the eccentricity of material coil mass, and the change of production environment temperature and humidity will also affect the tension the fluctuation of the whole machine.

5. The driving mechanism of the slitting machine (such as guide roller, floating roller, flattening roller, etc.) have imbalance and air pressure instability and other factors.

6. The change of speed during cutting affects the change of tension: when the operation is accelerated or decelerated, the main motor speed changes. Firstly, the tension of the material from unwinding to rewinding is changed instantaneously, and the tension must be stabilized gradually after a period of small vibration of the material. The instability of this tension is reflected in the unevenness of the winding of the finished product and the concave and convex the phenomenon of the end face, which affects product quality.

Tension sensor detection is direct detection of tension, which is closely combined with machinery and equipped with a detection method of moving parts.The two sensors are usually paired and mounted on end shafts on both sides of the test guide roller. By detecting the applied load on both sides of the guide roller, the material belt causes the tension sensor sensitive element to produce displacement or deformation, so as to detect the actual tension value, and the tension data is converted into a tension signal and fed back to the tension controller.

A set of floating roller is installed in front of the tracking roller, and the position of the floating roller is detected by a potentiometer. The tension the control method is to keep the tension constant by maintaining the position of the floating roller. Magnetic powder clutch is used to control the rotation moment of the coiling roller to achieve tension control: the magnetic powder clutch is composed of the active part and the driven part.It is connected with the coiling roller through universal coupling and other driving mechanisms and the magnetic powder is filled in the middle as the moment transmission medium.

A magnetic field is formed by passing a certain current into the excitation coil. The magnetic powder is magnetized.

After magnetization of the magnetic powder attracted to each other to form a chain pattern, actively part in constant speed rotation, the coupling between magnetic powder relay to form a circle tangential force, the tangential force, and magnetic particle diameter of the product is driving the rotation of the driven part of the winding torque, in the continuous rotation of the output torque from the active part coupled to the driven part, so as to achieve the purpose of tension control.

The magnetic powder tension brake is mainly used to control the unwinding speed. Its working principle is: a shaft coupling is installed in the magnetic powder brake, as well as the input and output components with the magnetic coil. Below the magnetic coil is a circular groove, and below the groove is a circular rotor, the output part. The annular groove is located in the center of the output unit and is filled with magnetic powder.

When there is an excitation current in the magnetic coil, the coil produces a magnetic flux that causes the magnetic particles to align in the direction of the magnetic field, thus creating damping between the input and output components, transmitting the torque.If the tension and speed applied to the aluminum foil are increased or decreased, the tension and speed can be effectively controlled by changing the magnitude of the excitation current, or by changing the current value or voltage the value applied to the coupling coil by the amplifier.

Tension control inverter system，the characteristics of the system is to cancel the tension controller, the tension controller functions and parameters, such as the coil diameter calculation function, coil diameter output, the system is accelerating, decelerating, stopping to overcome the inertia of the system, the corresponding torque static and dynamic torque compensation.

Film breaking alarm function; When the system stops abruptly, it can effectively prevent the function of "flying car". All of them are built into the inverter and the inverter is used as a tension controller, which makes the tension of the whole process very stable.