High Speed Influencing Factors Of Electronic Shogging System For Warp Knitting Machine

Compared with the warp knitting machine of mechanical shogging system, warp knitting machine of electronic shogging system is more adaptable to the market requirements of small batch and many varieties. It has a series of advantages such as wide adaptability, convenience to change pattern, have strong power to produce pattern, which promote the warp knitting machine into an electronic intelligence controlling era instead of mechanical controlling.Throughout the warp knitting industry at home and aboard, the high-speed warp knitting machine of electronic shogging system is more expensive and slow than the warp knitting machine of pattern wheel. what's more, the domestic warp knitting technology is relatively less developed than foreign countries. Therefore, the study to develop an electronic shogging system with higher speed and lower cost will be the direction of warp knitting technology.This paper takes the rotating servo motor'control system as the research object. The research is done from two aspects, which are mechanical transmitting system and electronic controlling system, to analyze various influence factors for the high speed of the electronic shogging system. Concrete analysis content and methods are as follows:First., the paper takes the warp knitting machine of HKS4 type for example, which is produced by Karl Mayer company in German. The co-ordination discipline and process requirements of loop-forming element are investigated to calculated the allowable shogging time of guiding bars. There are three requirements for the electronic shogging system of the warp knitting machine. They are high-speed, high-responding and high accuracy positioning.Then, deep research about electronic controlling system and mechanical transmitting system was done. In the respect of mechanical transmitting system, the mass, stiffness of the shogging system and other aspects that have effects on the high-speed characteristic are researched separately. It sums that using carbon fiber reinforced composite as the materials of guide bar is beneficial to the high speed. The influence factors for the weak-link position of the mechanical transmitting system are also found out. After carrying on an investigation into the system feedback approach, system gain, system control modes and other aspects, it turns out that; using semi-closed loop controlling model is more suitable for warp controlling system; system gain parameters has a great effect on positioning time and the location accuracy of shogging movement; using speed controlling mode is more advantageous to operation controlling of servo motor than position controlling mode, which is also more adaptable to the requirement of high speed.Then, the impact of ball screw on shogging movement is studied. It have shown that using the"fixed-fixed"installation can increase the speed of the shogging movement; the length of ball screw has been designed; the requirements for the ball screw lead and diameter in the shogging movement are also researched; through the checking calculation on the axial stress, radial stress and the allowable maximum rotating speed of the ball screw, it bear out the ball screw I selected can meet the requirement; through the designed trials, the applicability of the selected screw and the correctness of the approach are tested. the paper analyzes the influences of the rotary servo system on the shogging system and do research on servo controlling technology. After studying on the mechanical properties of the shogging system, the requirements of shogging system on the inertia, torque and maximum speed of servo motor are found out.Finally, Servo-control transferring function is gained by researching the servo-control model. The paper also has designed a system structure based on common PID controlling. In this structure, the feedforward controlling of speed loop and current loop has been introduced. Through simulation experiments in matlab, it turns out that using feedforward PID controlling can improve the commands tracking performance of the controlling system effectively.