Design Of Detection System Of Jacquard Circular Knitting Machine Needle Selection Signal

Jacquard circular knitting machine is a high-end weft knitting machinery, mostly takepiezoelectric ceramics needle selector as an executed devices. Up to now, most jacquard circularknitting machine control modules are designed on the base of the open-loop control mode,including needle selection signal module. The quality of needle selection signal directly affectsthe quality and efficiency of weaving. With the improvement of living standards, people havemuch higher demand in wearing, and the textile products colored in the complex pattern ofknitting also increase quickly.However, the more complex pattern weaving requires circularknitting machine with more sophisticated control systems, so it is necessary to detect the needleselection signal and make a feedback. At present, most researches focused on the study ofproperties of piezoelectric ceramics, the relative lack of control and signal detection research interms of power. So, the research of jacquard circular knitting machine needle selection signaldetection system not only helps to improve the reliability of circular knitting machine knitting,enhance the core competitiveness of Chinese textile machinery,but also provides reference forthe next generation of composite-controlled models research.In this paper,take multi-function jacquard circular knitting machine needle selection signalas the object of study,and study the mechanism of needle selection signals,including pattern datastructure, needle selection data analysis,output data and so on,also introduce the piezoelectricceramic needle selector operating characteristics in detail,and at last make a design combinedwith the basis theory of overall and the actual needs.There are two subsystem named as thehigh-speed signal line detection system and a drive circuit reliability detection system based onpiezoelectric ceramics needle selection.High-speed signal line detection system describes the minimum system CPU, Flashmemory circuit, SD card read-write circuit, parallel bus, RS-485serial bus and USB bus drivercircuit and the corresponding software design. The two subsystem use ARM processor to ensurethe processing speed and the real-time of detecting system. RS-485serial bus circuit and parallelbus collect data and after processed the result upload PC via USB-CDC way by the USB buscircuit. The detecting system finish two functions included comparing the data and display thegraph. According to the experimental tests, the designed system have strong real-time and graph imaging, and meet the design requirements. The piezoelectric ceramic needle selection systemdescribe signal sending circuit, signal acquisition circuit and the signal selection circuit. Discussthe RS-485communication protocols, signal fault code, and the drive code of underlying signalacquisition and processing, and introduce a kind of test probe to collect signal. By test samplesexperiments, the results show that the system has high reliability and fault signal classification ofcertain capabilities, and indirectly help to detect needle selection signal.This needle selection signal detecting system works stablely, and the test results are reliableand intuitive.It shows good engineering applications.