Application of general-purpose frequency converter on air spinning machine

Application of general-purpose frequency converter on air spinning machine Wang Haiming (Shaanxi Tianwang Xingye Group Co., Ltd., Xianyang 712000, Shaanxi Province) proposed a scheme to replace the gearbox with a frequency converter, and the effect is very good.

1 Overview The general-purpose inverter is a combination of a microcomputer and a power semiconductor, and has various functions, and these functions are mainly realized by software. At present, the advanced frequency converter has a variety of adjustment and operation functions, and can be applied to any kind of mechanical AC frequency conversion speed regulation. The result of high integration makes the reliability of the inverter greatly improved, and it can generally operate without failure within 3 to 5 years. The AC asynchronous motor itself is a durable product, so the combination of the two makes it more reliable. In addition, the inverter also features strong protection and easy maintenance. General-purpose inverters have at least 14 types of error detection, fault detection, and fault protection. When the power supply overvoltage, undervoltage, overheating of the motor, overcurrent during the rise and fall, and short circuit of the output short circuit are encountered, the inverter will immediately stop the shutdown. The maintenance personnel can immediately determine the cause of the fault and quickly process it through the fault code or character provided on the inverter display.

2 Problems existed. Our company introduced the air spinning machine from the Czech Republic in 1988. After more than ten years of operation, the mechanical wear is more serious, and the maintenance cost is high, especially the yarn-changing gearbox. The yarn-changing gearbox mechanism is complicated, requiring high manufacturing precision, heat treatment conditions, and assembly quality, and the components are expensive. In the production process, the chain and the sprocket are easy to wear. Generally, it needs to be replaced once in less than one year. The maintenance is very troublesome; the failure often stops, which seriously affects the output.

3 transformation plan and method In order to solve this problem, we borrowed the experience of Shandong Demian Co., Ltd., and chose a 3kW AC motor to replace the yarn-changing gearbox. The motor is driven through the belt and directly connected to the inverted sub-axle box and the cotton feed gearbox. A FRN3.0G11S-4CX Fuji inverter is selected and installed on the left door of the electric control cabinet. Because the inverter is small in size and light in weight, the space inside the control cabinet is relatively large, so the installation is very convenient. In the design of electrical circuits, try to use the original electrical switches and fuses in the control box; the speed adjustment still uses the two buttons on the original operating panel to control the speed increase and decrease. See the electrical circuit diagram.

The conclusion of the frequency conversion speed control system line is small (only about 4,000 yuan), and it has the characteristics of balanced operation, safe and reliable, and simple transmission structure. The effect is very good.

Not only reduce the stoppage time, improve production efficiency, reduce the labor intensity of maintenance work, reduce maintenance costs, and the original operation procedures of the blocker are unchanged, which is worth promoting.