Today, we will introduce the transmission system of the paper cutter.
1. The composition of the transmission system of the paper cutting machine:
The paper cutter is composed of arc roller, cutter, conveyor, paper roller and cutter. The main function of the roller is to stretch the paper page to prevent wrinkling, so the speed is synchronized with the paper industry. The cutter usually needs about 1.2 times faster than the paper. The conveyor belt is mainly the finished paper page and the paper stacking. Therefore, the four moving point control requirements are relatively low, which can be controlled by variable frequency drive open loop control, and the speed difference control of the main transmission speed chain can meet the requirements.
Two. The basic control system structure of the paper cutter (as shown):
The RS485 communication between PLC and frequency converter is used to control the paper feeding roller and paper cutter, and the operation control of the paper cutter is realized through the touch screen. The control between the paper feeding roller and the cutter of the paper cutter is in fact a high precision speed ratio control. We only need to control the cutting length in the error range. It's not like printing presses that require precise position control. Therefore, the control of paper feeding rollers and paper cutters adopts high precision position control mode, and the high-speed pulse is output by PLC as a given.
Three, servo control design the basic way of servo control.
It is mainly divided into speed mode, torque control and position control.
The 1. speed mode: the speed of rotation can be controlled by the input of analog quantity or the frequency of the pulse, but it can not do the positioning control directly. The external loop PID control of the external upper control device can also be positioned, but the position signal of the motor or the position signal of the direct load must be given to the upper feedback to do the operation. It can also be widely used in the speed regulation of the transmission system. Because the control between the paper feeding roller and the cutter of the paper cutter is in fact a high precision speed proportional control, and it can also be used in the control of the paper cutter.
2. torque control: the torque control mode is to set the output torque of the motor shaft by the input of the external analog quantity or the value of the direct address, and can change the set torque size by changing the simulation amount immediately. This mode is mainly applied to the winding and rewinding of the material with strict requirements. In the device.
3. position control: the position control mode usually determines the rotation speed by the frequency of the external input pulse, and determines the angle of rotation through the number of pulses, and some of the servos can assign the speed and displacement directly through the communication mode. Because position mode can control speed and position very well, it is generally applied to positioning devices. Application areas such as CNC machine tools, printing machinery and so on.