Analysis Of The Oscillation And Turbulence Process Of The Four-bar Beating-up Mechanism With Motion Dual Clearance

With the constant increase of the loom's speed and the requirement for variety of fabric,especially the heavy fabric.the higher requirements are put forward to the beating-up mechanism of air-jet looms. The rotate speed of the Four-bar beating-up linkage has been improved from 450r/min to 850r/min,or even higher, the present machine has a lot of malfunction in the process of rotating. For example, when manufacturing heavy or wide fabric, the rockshaft may come up with crack, even rupture, and the 110 axletree shows serious abrasion, etc. .Therefore, the beating-up linkage must be studied by dynamics method and the current problems must be solved as quickly as possible.This article was written from the view of dynamics analysis to analyze dynamics characteristic. Starting from the oscillating measure of the loom frame and the lay of 1515 shuttle loom and ZA-style air-jet loom, I compared the structure, kinematics parameter and dynamic performance of the two kinds of four-bar linkage beating-up mechanism. Also I discussed in this paper the evolvement process from No. 1515 shuttle loom to the shuttleless loom from the dynamics and the optimization of dynamic characters,and got the design principle of four-bar linkage beating-up mechanism.I made use of method of finite element to establish the model of Kineto-Elasto Dynamics and calculated the regular frequency of ZA-sryle air-jet room through MATLAB and changed parts of the design parameter to discuss the changes of mechanism's regular frequency under the circumstances of mass reduction with a view to offer improved idea for the improvement of mechanism's performance.On the basis of kinematics and kinetic analysis,this article ulteriorly analyze mechanism dynamics with clearance caused by motion dual clearance of mechanism. In this article I took four-bar linkage mechanism as the research object and through the picture of oscillation line I discovered the location where angular acceleration of the linkage equaled to zero was the frequent area of strong oscillation of crank-rocker mechanism of sliding bearing with clearance. I made use of the journal's central track of sliding bearing with clearance to investigate and analyze the oscillation characteristic of the four-bar mechanism of motion dual clearance and discovered that the strongest oscillation took place when the angular acceleration of the linkage was zero and the eccentricity of central track of journal was less, than 0.1. Also I investigated the stability of the location of journal's static balance and the characteristic of the oscillation of oil-film bearing journal through kinetic equation.Written by Ouyang Bin (Textile Engineering) Supervised by Senior Engineer Zhu Zhangchen...