Li Qiang, Shanghai Electromechanical Business Department, Delta Electronics Co., Ltd. Automatic cutting tables are specialized equipment used for cutting rolls of materials to a fixed length, typically used in the production processes of transparent tape, self-adhesive tape, plastic film, and paper rolls. This article describes the application development of the electrical control system for automatic cutting tables based on Delta's integrated automation technology. 1 Introduction The main purpose of automatic cutting tables is to cut materials such as transparent tape, self-adhesive tape, plastic film, and paper rolls to a fixed length, slicing a full roll of wide material into smaller rolls according to a set width. For example, commonly used transparent tape is cut using this equipment. The cutting width can be set on the human-machine interface (HMI). Multiple working modes can be established on the HMI, each including two parameters: set width and number of cutting blades. For example, if the customer selects mode 1, the system will automatically cut according to the width set in mode 1, and automatically stop after the set number of cuts is reached. If mode 10 is selected, the system will automatically stop after completing the number of cuts set in mode 10. The difference between dual-servo and single-servo systems lies in the fact that single-servo systems control the movement of the cutting table via a servo drive, while the feed and retraction are controlled by a hydraulic system. Dual-servo systems use servos not only for the movement of the cutting table but also for the feed and retraction. The feed length can be set via the human-machine interface, improving cutting accuracy. [IMG=Figure 1 System Block Diagram]/uploadpic/THESIS/2007/11/2007111610313829295D.jpg[/IMG] Figure 1 System Block Diagram [IMG=Table 1]/uploadpic/THESIS/2007/11/20071116103150288720N.jpg[/IMG] Table 1 Automatic cutting tables are divided into single-tube and dual-tube types. Shanghai Electromechanical has successful cases with both types of equipment, and they are already in stable use at customer sites. Supporting machinery manufacturers are also using Delta's products normally. Due to increasingly fierce competition in the industry, in order to further improve the equipment's grade and meet higher precision requirements, we provided the customer with a control solution for a dual-servo automatic cutting table. After two days of development and debugging, the equipment was successfully developed, further solidifying the customer's confidence in using Delta products. At the same time, the performance of Delta servos was also recognized by the customer. 2. Electrical Control System Design 2.1 System Composition The system composition is shown in the system block diagram (Figure 1). 2.2 Hardware configuration of the electrical control system based on the Delta technology platform is shown in Table 1. 3. Control System Design of the Dual-Servo Automatic Cutting Table 3.1 Process Main Analysis The dual-servo automatic cutting table is driven by two frequency converters. One drives the spindle motor; the other drives the circular cutter (cutting blade). The two servos are coaxially connected to the lead screw. One controls the positioning of the cutting table, i.e., length setting. The other controls the feed and retraction of the cutter. The frequency converters are controlled via RS485 communication, providing the spindle and circular cutter speeds. The servos use Pt mode for positioning. Based on the customer's requirements, we provided single-segment and continuous control modes and 10 operating modes. If there are special needs, the operation mode can be expanded to dozens of modes. Each operation mode includes two parameters: width setting and number of cuts setting. 3.2 Process Control Design Customers pre-set the required tape width and the number of cuts required for that width in the parameter table according to production requirements. These two parameters are linked to the power-off retention register in the PLC. If the operator selects single-segment control mode, after entering the mode number on the HMI, the system automatically retrieves the corresponding parameters (width and number of cuts). After startup, the cutting table begins to move laterally at a fixed length via a servo. When it reaches the set width, the lateral movement of the cutting table stops, and the longitudinal movement of the cutting table is controlled by another servo. When the cutting table moves to the front limit, a timer starts to ensure that the tape is completely cut. Once the timer expires, it automatically returns to the rear limit switch and stops. If the number of cuts set for this mode is not zero, the above actions are repeated until the number of cuts equals the number of cuts set for this mode, at which point it automatically stops. If the number of cuts set for this mode is zero, the system does not operate. If the operator selects continuous control mode and enters the mode number on the HMI, the system will automatically cut according to the width and number of cuts set in Mode 1 after startup. Once Mode 1 is complete, it will automatically cut according to the width and number of cuts set in the next mode. If the set number of cuts for a given mode is zero, the system will automatically skip that mode and proceed to the next mode, until all set modes have been cut, at which point it will automatically stop. For example, in continuous mode: if Mode 10 is selected, the system will cut according to the parameters set in Mode 1 after startup. Once Mode 1 is complete, if the set number of cuts in Mode 2 is not zero, it will automatically cut according to the width and number of cuts set in Mode 2. If the set number of cuts in Mode 2 is zero, the system will automatically skip Mode 2 and cut according to the parameters set in Mode 3. This process continues until the width and number of cuts set in Mode 10 are completed, at which point the system will automatically stop. The lateral movement speed of the cutting table can be set on the HMI. The lateral movement speed has two speeds: initial speed and normal operating speed. The switching between the two speeds is accomplished through a timer. The switching time between the two speeds is set on the HMI. Before normal production, the system requires tool setting to ensure the circular cutter can cut the material. This necessitates rapid tool feed and retraction, with the circular cutter cutting at full speed just before contacting the material. After cutting, the cutter retracts quickly. To meet these requirements, I designed a very user-friendly operation for the customer. Before starting, the feed speed and cutting speed are set on the HMI (Human Machine Interface), and then the tool is manually fed. The manual feed starts at a high speed; once the manual feed is released, the circular cutter quickly retracts. The system automatically remembers the duration of this manual feed and displays it on the HMI. During normal operation, the circular cutter approaches the material at the set feed speed each time, automatically retrieving the time before tool setting. Once the time is up, it cuts at the set slow speed. The operation is simple, convenient, and highly user-friendly. [IMG=Figure 2 Overall Machine Image]/uploadpic/THESIS/2007/11/2007111610320573141Z.jpg[/IMG] Figure 2 Overall Machine Image [IMG=Figure 3 Electrical Control Image]/uploadpic/THESIS/2007/11/2007111610322188879D.jpg[/IMG] Figure 3 Electrical Control Image 3.3 Process Control Flow The sequence of the system control flow is as follows: First, the chuck moves. Before the chuck moves, the rocker arm cylinder moves upward. After reaching the limit, the chuck and ejector pin move to clamp the spindle. Then the spindle and the circular cutter can start cutting. If the "Stop All" button is pressed during automatic operation, the spindle and the circular cutter stop running. Then the ejector pin retracts, the chuck opens, and after the ejector pin returns to its position, the rocker arm cylinder moves downward and stops after reaching the limit. After continuous operation, the system automatically stops, retracts the ejector pin, and releases the chuck. The rocker arm cylinder lowers to its final position. Then, when changing rolls again, if the chuck is activated, the cutting table automatically returns to its origin, the rocker arm rises to its final position, the ejector pin is fully engaged, and the chuck clamps the spindle, facilitating roll changes after the entire roll of tape has been cut, thus simplifying operator operations. 3.4 Automatic Memory Function: During the entire automatic cutting process, if any malfunction occurs or the operator manually stops the machine, the system records the currently executed mode number and the number of cuts completed. If the malfunction is resolved and the system restarts, it continues cutting according to the mode before stopping. The above describes the automatic cutting state. 3.5 Automatic Tool Setting Function: In manual mode, an automatic tool setting function is provided. That is, in the event of a malfunction or poor quality of the previous cut, while the machine is stopped, the cutting table can be automatically moved backward or forward by one width according to the width set in the current mode by pressing the indirect return or indirect forward button on the HMI or control panel, achieving automatic tool setting. Manual tool setting is also provided. 3.6 Key Technology Design (1) Setting and Calling of Mode Parameters All mode parameters (width setting, number of cutters setting) are stored in the continuous power-off retention area of ​​the PLC, and the corresponding addresses in the PLC are all double words. If the width setting in mode 1 corresponds to D500 in the PLC, then the number of cutters setting corresponds to D502 in the PLC, and the two parameters in mode 2 correspond to addresses D504 and D506 in the PLC. Therefore, indexed addresses can be used for addressing. The mode number input corresponds to D570, and the parameter calling function can be realized through the following program. SUB D570 K1 D90 MUL D90 K4 D92 MOV D92 F2 ADD D92 K2 D160 MOV D160 F1 DMOV D500F2 D192 //Set width MOV D500F1 D190 //Set number of cuts (2) Length calculation: The lead of the lead screw is 10mm, the electronic gear ratio is 2, the servo pulses are 10000/revolution, and the servo is coaxially connected to the lead screw. The width is set to 2 decimal places. Therefore, the relationship between the set width and the required pulses can be deduced as follows: Required pulses = 10000 * set width / 100 * electronic gear ratio * lead = set width * 5 (3) Mode conversion: The current number of cuts is based on the retraction position, and is incremented by one each time. When the number of cuts is equal to the set number of cuts, the mode is automatically incremented by one. Thus, the running parameters are automatically converted to the parameters set for the next mode. (4) The speed of the communication spindle and the speed of the circular cutter are communicated via RS-485, and the frequency converter is given by the PLC. 4 System Debugging 4.1 System Debugging (1) Complete the logic part of the entire control through debugging. Ensure that the basic logic action is correct. (2) Debug the communication program of the frequency part of the spindle and the circular cutter. (3) Use manual mode to make the servo run in JOG mode. (4) Servo parameter settings: 1-00: 2; 1-01: 0; 1-44: 2; 2-08: 12; 2-10: 1; 2-15: 0; 2-16: 0; 2-17: 0; Adjust 2-00; 2-02; 2-04; 2-25; 2-26 according to the specific running effect of the servo; At the same time, adjust the 1-08 parameter accordingly to ensure that the servo runs more smoothly when running at high speed. Set this parameter according to the specific situation. (5) Determine the running direction of the servo and make it consistent with the requirements. (6) Connect the grounding on the servo drive as required, and connect the grounding wire on the inverter to a reliable earth. Otherwise, the servo may malfunction due to interference from the inverter. If there is no reliable earth on site, reduce the carrier frequency of the inverter accordingly. If there is a 24V power supply in the cabinet, consider connecting the grounding wire of the inverter to the 24V- of the switching power supply to reduce interference. 4.2 See Figure 2 and Figure 3 for pictures of the whole machine. 5 Conclusion Delta Electronics is mainly a supplier of automation equipment and services with the greatest growth potential in China. Delta's inverters, encoders, human-machine interfaces, PLCs, servos, temperature controllers and other electromechanical products and technical services cover the main automation technology fields. Delta Electronics' parent company is Delta Electronics Group, a world-renowned multinational electronics manufacturing company. Delta Group has a large-scale production base in Wujiang, Jiangsu, providing comprehensive manufacturing of electromechanical products. Delta Electronics' service system covers the whole country. Delta is also the world's largest supplier of power management systems. As a well-known manufacturer in the industrial control industry, we can provide comprehensive solutions for customers in various industries by applying our products. Optimal product cost-effectiveness and comprehensive nationwide and even global warranty services guarantee customer interests. (Proceedings of the 2nd Servo and Motion Control Forum; Proceedings of the 3rd Servo and Motion Control Forum)