Abstract: This paper introduces the process automation design principle of a new high-speed drawing frame. The project consists of an economical and mature control system composed of a DELTA human-machine interface, an ES series programmable logic controller, an A series servo system, and an E series frequency converter. The project has been successfully applied to drawing frames in textile machinery plants. Keywords: Drawing frame, system integration, HMI, PLC, frequency converter 1 Introduction The drawing process in cotton spinning is a key process for improving spinning quality in modern spinning technology. The raw material input to the drawing process is the "raw sliver" with the primary form of yarn from the front-end carding process section. The finished product of the drawing process is the "finished sliver" that has undergone four processes: drawing, traction, mixing, and forming. The "finished sliver" is usually sent to the back-end roving frame after coiling. The key technology of mechatronic drawing frames is to solve the contradiction between drawing speed and drawing quality, and to process the "raw sliver" quickly and efficiently. The automated high-speed drawing frame developed in this project is mainly used for the drawing and stretching of combed, carded cotton, chemical fiber, and blended processes with a sliver diameter of less than 76mm. This improves the uniformity of long sliver segments and the straightening and parallelism of fibers, resulting in a more uniform blending of fibers of different qualities within the sliver. It is generally used as the final step after the combing machine, producing better sliver quality, particularly in reducing weight unevenness and improving the evenness (CV) value of the yarn. Its quality indicators meet or exceed relevant national standards, greatly benefiting the yarn quality of subsequent roving frames, spinning frames, and automatic winding machines. 2. Process Principle The drawing process can be summarized as four functions: drawing, traction, blending, and sliver formation. Because the sliver produced by the carding machine has a high unevenness and disordered fiber arrangement, the quality of the yarn spun directly is very poor. The above steps effectively improve the evenness of the yarn, i.e., the fiber state. Drawing... Six to eight cotton slivers are fed together into the drawing frame to form a single sliver for drafting. The sliver is stretched and thinned to its original length while altering the fiber state, effectively controlling the quantitative mixing of the finished sliver. Repeated mixing further achieves the mixing of individual fibers, ensuring uniform sliver composition and stable yarn quality. The finished sliver is then regularly placed in a sliver can using a coiling reel for easy handling and use in the next process. 3. Project Design 3.1 Design Overview Currently, the design speed of domestically produced new high-speed drawing frames is generally 600-800 m/min or higher, with actual operating speeds mostly between 360-420 m/min. Most domestically produced new high-speed drawing frames currently use double-eye sliver output, with a few using a single-eye structure, but these are mostly used in models equipped with the Swiss Uster self-regulating leveling system. The new high-speed drawing frame has undergone significant electrical changes, eliminating some original mechanical structures and using extensive electrical control, greatly improving machine performance. The appearance of the new high-speed drawing frame is shown in Figure 1. 3.2 The design features dual-eye output; suitable for fibers 22-76mm; maximum mechanical speed 800m/min; employs an open-loop self-regulating leveling system to achieve short-segment self-regulation, improving sliver unevenness and evenness CV% value, resulting in high-quality sliver; extensive use of synchronous belt drives for "gapless" transmission, low noise, stable drafting, and reduced sliver unevenness; each eye, except for the automatic bobbin changer, operates independently, eliminating interference with the drafting drive; features a three-up, three-down dual-zone curve drafting system with guide rollers and pressure bars; upper cleaning uses a rotating cloth belt or floating metal bar, while lower cleaning uses a reciprocating oscillating nitrile scraper; pressurization options include pneumatic and spring pressurization, with adjustable pneumatic pressure; utilizes programmable logic controllers (PLCs), touchscreen displays, and variable frequency speed control; and includes provisions for a central network connection. The machine features a remote fault diagnosis function; a variable frequency speed control for the main motor ensures smooth start-up, adjustable acceleration and deceleration times, and the ability to select the optimal starting state; a touchscreen display enables human-machine interaction with both Chinese and English options; the pressure cradle's lifting and lowering is controlled by cylinders and buttons; the tension of the four main zones—coil, front zone, rear zone, and guide zone—can be adjusted in multiple levels without keyless connections, improving its spinning suitability; the suction, upper, and lower sections are each connected to the cotton suction box via separate air pipes, automatically removing cotton from the box to maintain uniform suction and prevent excessive cotton accumulation from affecting the suction effect; it has automatic cotton stripping, automatic pressure release, automatic bobbin changing, and automatic lubrication functions, eliminating the need for a process change wheel and simplifying maintenance and operation; the automatic bobbin changing mechanism features a positive sliver breakage mechanism for reliable operation; advanced processing technology for key components and high precision ensure high-quality sliver; and the product has a novel and attractive appearance. 4. High-Speed ​​Drawing Frame Based on Delta Mechatronics Technology The new high-speed drawing frame utilizes a full range of Delta mechatronics technology to achieve a single automated platform for process control. The control system block diagram is shown in Figure 2. The project uses a DVP60ES00R2 PLC to control the entire machine's operation, and is equipped with a DOPA57GSTD or DOPAS57BSTD touchscreen. The PLC and touchscreen communicate via RS232, displaying parameters such as output, strip speed, rotation speed, fixed length, and shift using Chinese characters and graphic symbols. Faults are also displayed in real time, making control more user-friendly, facilitating both machine operation and management. Data exchange and communication control between the PLC, servo drives, and E-series frequency converters are achieved via MODBUS RS485. Figure 2 shows the control system block diagram. The main drive of this machine, namely the first roller, uses a Delta VFD055E43A frequency converter to drive the variable frequency motor. A Delta ES3-06CG6941 optical encoder sends the speed signal to a subsequent Delta ASDA1521MA servo drive unit. The servo motor drives the second and third rollers. The servo receives encoder pulse signals, which are then processed by the PLC based on the difference between the standard quantitative and the detected quantitative values. The PLC then sends commands via MODBUS bus to change the servo electronic gear ratio, thereby dynamically changing the draft ratio until the detected quantitative value meets the national standard process requirements. Previous models were based on single-board computer control with digital tube display, resulting in a cumbersome system interface and frequent circuit board replacements due to the instability of the electrical control system. The application of Delta's human-machine interface, ES series programmable controllers, frequency converters and servo drives, encoders, etc., to the control of drawing frames has greatly improved the reliability of the machines. Because the previous light and heavy gear mechanical devices are no longer needed, the total draft ratio can be changed simply by dynamically changing the servo electronic gear ratio. This makes the machine system simple, reliable, easy to operate and maintain. When changing the type of sliver, the draft ratio is adaptively adjusted by the machine, which reflects the advantages of Delta's product integration in OEM equipment. It has extensive storage and display content, self-adjustment, tension control, and can easily realize automatic statistics of shift/total output, data retention after power failure and other system functions. 5. Conclusion Since its successful trial use at Jiangsu Jiangyin Yuhua Chemical Fiber Co., Ltd. in May 2007, this model of textile machinery has been widely promoted and applied in many textile enterprises across the country, such as Fujian Jinyuan Textile, Sichuan Tianjiao Textile, and Jingmen Textile, due to its excellent cost performance. To date, more than 120 sets of machines have been put into commercial use. The product has been welcomed by yarn mills, received positive market feedback, and brought significant economic benefits to the textile machinery factory.