Study On Density And Arrangement Of The Cotton Combing Cylinder Needle Tooth

The combed cylinder is the core component of comber.Different raw materials,requirements of combing quality and parameters of combing process need to match different density and arrangement of needle tooth of cylinder.But in the actual production,with varieties of raw materials,different requirements of combing quality and parameters of combing process of different enterprises,it is very difficult to design and match appropriate density and arrangement of needle tooth of cylinder.At present,Generally the right cylinder is selected through practice experience,but for some new materials or special combing quality requirements need a lot of optimization test to spin yarn,and evaluate the carding effect through yarn indicators,Generally it will cost a lot of labour and material resources.So,it is very important to study the design method of density of needle tooth of cylinder and the simple evaluation method of arrangement effect of needle tooth of cylinder,according to the principle of combing machine and the structure characteristics of combing cylinder.This topic discussed the design method of total number of combing cylinder teeth,optimization method of density configuration of density of needle tooth of cylinder and evaluation method of arrangement effect of needle tooth of cylinder.First of all,a model of total number combing cylinder teeth is established,according to the relationship between total number of combing cylinder teeth and the type of raw cotton,related parameters of combed quality,and an example of design method of the total number of teeth is cited.A mathematic model of position coordinates of cylinder needle teeth is established,according to parameters of sawtooth size of cylinder teeth In the sawtooth section position andthe slope angle of tooth.And using Matlab software to quickly calculate lateral every point on the fiber carding cycle projection of blade number and its poor and CV value,And an intuitive evaluation method of cylinder needle tooth arrangement effect is raised,by using Matlab software to quickly calculate the number of projection teeth at each point of cotton layer transverse in a carding cycle.In the end,the infulence of cylinder tooth configuration of the carding areas on carding effect is studied,using the cylinder with similar total number,by spinning contrast test.The results show that: the selection of total number of combing cylinder teeth depends on cylinder carding degree,combing noil rate,Cotton fiber fineness,the lap quantitative,the feeding way,the feeding length and the separation distance.The total numbers of combing cylinder tooth,which are suitable for 32 s semi-combed yarn,40 s common combed yarn and 60 s high-grade combed yarn respectively,were calculated according to mathematical model of total number of cotton combing cylinder tooth.Under certain conditions,when the needle tooth density of any combing area increase,the number of teeth acting on each fiber increases,carding degree of cylinder increases,the effective length of fiber in the combed slivers is increased,short fiber content of combed slivers decreases,and the IPI values of yarn conventional faults are obviously reduced,and yarn evenness is improved.When the total number of teeth of the combed cylinder is similar,increasing the tooth density of different carding areas,has different influences on the yarn quality indicators.And when increasing the tooth density of the first carding area,yarn neps,thicks and thins are obviously reduced.When increase the amount of needle teeth of the rear combing area,the fibers are overly combed in the area,fiber are easily to be fatigue,and fatigue degree will be more serious in the subsequent drawing process,so the yarn strength has a tendency to decrease.(5)The projection distribution of the combed cylinder needle in the transverse direction of the cotton layer depends on the parameters such as the length and width of the section of needle tooth,horizontal pitch,the circumferential pitch and the inclination angle of the tooth along the transverse direction of the cotton sheet.The effect of the pinning arrangement of the cylinder can be reflected by the number of times that the needle teeth are projected in the transverse direction of the fiber layer and the CV value.the more of the times that the needle teeth are projected in the transverse direction of the fiber layer,the stronger of combing effect of the cotton layer at each point,the moreuniform of cotton layer of the points by the combing.