Application of VEICHI AC200-C in CNC Lathe
Ⅰ. Overview
The technical level of CNC Lathe and its percentage of output and total ownership of metal cutting machine tools, is one of the most important symbols to measure the national economic development and industrial manufacturing level. CNC lathe is one of the main varieties of CNC machine tools, which occupies an important position, and has been paid much attention to by the countries all over the world for decades, so that it has been developed rapidly. Spindle is an important part of the lathe structure, which plays an important role in improving the processing efficiency, expanding the materials range, and improving the quality. The majority of economical CNC lathes can not automatically change speed, and the lathe has to be stopped and then change speed manually in speed regulation. Mostly, the main drive system of full function CNC lathe adopts stepless speed regulation. At present, there are two kinds of frequency spindle system and servo spindle system. Generally, the spindle is driven by DC/AC motors with a transmission belt or a reduction gear inside the belt and spindle box (for greater torque). Because of the wide speed range and stepless speed regulation of spindle motor, the structure of spindle box is greatly simplified. Therefore, lathe specialized inverter is widely used in CNC lathe due to the high cost efficient. And VEICHI inverter has rapidly risen on the application of CNC lathe with its unique performance and superior cost efficient.
Ⅱ. Process Requirements
1. When the CNC lathe is working on the workpiece, the feed amount is large and processing speed is low. Due to the uneven surface of the workpiece, there will be an impact load;
2. When the lathe is finishing, the feed amount is small, and the machining speed is high to ensure the machining efficiency;
3. It requires the spindle motor outputs large torque at low speed, and could run at high-speed overclocking at the same time;
4. High linearity of the given frequency signal and actual motor speed, and it is less disturbed by load;
5. Fast DEC stop;
6. Self tuning of motor parameters.
Ⅲ. Solution of VEICHI Products
Spindle motor is driven by VEICHI AC200 high performance frequency inverter to meet the processing requirements and prolong the service life of the tool. Due to the adoption of leading flux algorithm, it can also output 100% torque smoothly even under low speed (low frequency) operation to meet various requirements of accessories. It can completely replace the traditional spindle structure of rolling bearings,and the spindle structure is simple and compact, which could realize the real stepless speed regulation. The speed of spindle is controlled by external analog signal and different speeds(such as rough machining, finishing, etc.) are required for different process requirements, therefore, different analog voltage signals can be output to the inverter by the CNC system to realize different speeds. At the same time, the start and stop signals are also controlled by the CNC system to improve the automation degree.
Ⅳ. Conclusion
The CNC lathe system with VEICHI inverter could achieve steady and reliable operation, and gain high economic benefits for customer. And VEICHI overall solution is highly praised by customers through the actual production test. The specific advantages are as below:
1. Excellent low frequency torque and weak magnetic ability, to meet the process requirements of different speed section of lathe spindle;
2. Fast ACC/DEC response and short positioning time, to improve the machining efficiency;
3.High spindle position accuracy, and position error ±1 encoder pulse, to fully meet clients needs;
4. Random carrier function, to effectively reduce the vibrations of machine tools;
5. Sealing design and high protection ability, to deal with harsh environmental challenges easily;
6. Cost advantage. The spindle system consists of general three-phase asynchronous motor and encoder, and save cost for customers when compared with AC permanent magnet servo.