Research On Application Of Inverter Controlled By Computer In Roving Frame

In traditional roving frame, the complex mechanical transmission and control system is adopted, which includes a pair of long prick wheel, quite a few groups of transforming gears, and springs, ratchet wheels and levers. Because of nonlinear error in the mechanical transmission system, the control on the tensile force of yarn is unstable, the precision of transmission is low, and the dynamic response is dull. Further more, calculation of process and changing varieties is very troublesome, the range of changing varieties is small, and the actual process value has some difference with the value in theory, which limits further enhance in output and quality of product.In this paper, we present a new rolling and forming control system based on inverter system including five motors controlled by computer. We cancel the forming mechanism, prick wheel shift mechanism, pulling gears and twisting gears, so as to simplify the roving frame. In detail, we adopt five motors to control the speed of front roller, back roller, spindle, tuber and lifter, to realize respective moving of each main driving part. The procedure controls the transmission rate. By detecting the speed of front roller directly, the software changes the speed of tuber and lifter. By controlling the speed of front roller and back roller, the software controls the pulling times and twisting degree. A raster ruler is fixed in the lifter. According to its reading, the computer controls the displacement of lifter, so as to reduce the displacement of lifter in every tier to ensure accurate forming.In this paper, after analyzing the theory of yarn rolling and forming, the mathematics model of changing motor speed and yarn rolling and forming is built. The holistic system project is presented. The hardware and software of control system is designed. Design of software is the emphases of this paper. Based on the mathematic model, I edit the software of controlling motor speed and yarn rolling and forming by Visual C++. The system responses rapidly, and controls the rolling process precisely. By it, the user can choose and save the basic process parameters easily. The real-time running status of roving frame is displayed. In order to control the precision of speed, the application of fuzzy-control arithmetic in speed feedback is also discussed.The system is validated by experiments. The results proves the feasibility of controlling by computer inverters to adapt the speed of five motors in roving frame. The system realizes the normal rolling of yarn, controls the forming of yarn precisely. By its nice interface, the user can set and change parameters, and changes the yarn types. So the system is valuable in actual process.