转杯内纱线形状及其张力分析

详细分析了转杯内纱线的受力情况，得出了求解纱线曲线形状和纱线张力的有效方法，求得纱段离开假捻盘表面进入出纱管时的分离点轨迹方程，并且指出：在纱线一周回转运动中，由于分离点不同，导致其切向角不同，进而影响到纱线曲线形状和纱线张力也跟着有所变化，但变化一般不大，故可把纱线运动看作为近似稳定来进行力学分析。     

转杯纺纱时杯内纱条的曲线形状和张力

本文导得纺纱杯内纱条曲线形状和张力的方程;利用这些方程可以比较可靠地求得纺纱杯内的纱条张力,解决杯内纱条张力不易测定的困难。根据这些方程作图,就可从这些图中简捷地求得杯内纱条的重要参数,用来计算纱条张力。另外,本文对正反向剥取形式也进行了分析探讨。     

转杯内纺纱曲线形状和张力

本文应用微分几何方法,导出转杯纺由任意曲线回转生成的假捻盘曲面上纱的形状和张力计算式,及纱曲线在假捻盘出口点的边界条件,以常用的1/4圆弧回转曲面为例作分析。最后,提供一个简便的剥离点纱张力计算式和转杯纺纱的充要条件。     

气流纱的拉伸特性研究

本文讨论气流纱的拉伸特性。Hearle曾对具有理想结构纱线的拉伸特性进行过比较完整的研究工作。本文则根据气流纱独特的成纱结构,对Hearle理论在气流纱中的应用作了一定的修正,并在此基础上对气流纱的拉伸特性作了分析计算。计算结果与实测结果基本相符。最后还从气流纱的应力-应变关系式中,就影响气流纱强力、初始模量以及断裂功等等力学特性的一些主要工艺参数进行了分析讨论。得出合理选用阻捻盘、很好控制捻度传递长度;合理设计与选用分梳及输棉机构,在不断改善单纤维供应的同时,尽量减少纤维损伤,提高纤维有效长度;适当提高纺纱张力,增加纤维转移等等都是改善气流纱强力等力学特性、提高成纱质量的有效途径。对工业用气流纱,还可通过合理设计凝棉槽,以提高气流纱紧密度的途径来提高气流纱强力。     

转杯纺杯内纱段剥离点张力的分析

采用功能原理的方法分析转杯纺的杯内自由纱段,对该纱段剥离点张力进行了研究,并讨论了影响剥离点张力的主要因素.     

倍捻锭纱线张力变化的分析计算

研究当气圈底盘（或称锭盘）是锥面盘时倍捻锭纱线张力变化的分析计算,求得该锥面盘的力学作用是可以降低纱线在刚脱离储线盘进入该锥面盘时的初始张力。并对一种弹头式张力调节器进行力学分析（这种调节器呈弹头形而非球形,故不能在空心锭内的锥座上自由转动）。然后再对空心锭内的纱线张力变化进行分析计算。     

TENSILE BEHAVIOUR OF ROTOR SPUN YARNS

This paper deals with the tensile behaviour of rotor spun yarns. Having regard to the spe-cial construction of rotor spun yarn, some modifications for Hearle's theory have been made inorder to apply Hearle' s theory to rotor spun yarn. The paper then goes into calculating thetensile curve and investigating the effect of main parameters and spinning conditions on thetensile behaviour of rotor spun yarn. It was found that the following facts are noteworthy forimproving the mechanical properties of rotor spun yarn: (1) Selecting suitable navel so as tocontrol the P. T. E. length within a reasonable range. (2) Improving the design of single fibresupply device to decrease the amount of spoiled fibre and hence increase the effective fibrelength. (3) Increasing spinning yarn tension without yarn break to enhance the fibre migrationratio. (4) For the rotor spun yarn of industrial use, it is the way to increase the yarn strengththat the rotor groove should be designed with the groove angle beneficial to decrease the yarnspecific volume.     

Yarn Tension at Peeling Point in Rotor Spinning

Based on the work and energy principle as explained inprevious literatures,the yarn tension at peeling point inrotor spinning was analyzed and calculated numericallyin this paper.The results show how raw materials,rotorspeed,rotor diameter,yarn linear density and navel de-sign can have certain definite effects on the tension valueat the peeling point.     

Relationship between Abrasiveness and Structure of Rotor and Ring Yarns

The friction and abrasion characters of yarn play veryimportant roles in the downstream processing and theend-use of products.With the development of rotoryarn and its application in the knitted products,theproblem of abrasion on the machine components causedby the processed rotor yarn has been paid more andmore attentions.This paper deals with the factors effectthe abrasiveness of rotor yarn and the comparison ofabrasive character between rotor yarn and ring yarn.     

Abrasion Resistance Comparison between Rotor and Ring Spun Yarn

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纱线绕在圆环面上的曲线状态及其滑动时的张力变化

本文主要分析圆环面上纱线卷绕时或滑动时的稳定曲线状态(短程线)以及纱线在圆环面上的实际包围角,根据这一包围角可以计算纱线在圆环面上滑动时的张力变化。     

纱路运行中局部悬链线的形态与张力

对于纺织生产过程中经常遇到的局部悬链线纱路,本文探讨了确定这种局部形态悬链线的具体数学表达式、纱线张力、曲线科率以及偏离直线最大偏距的计算方法,绘制了一系列曲线图来表示它们之间的变化关系.由于采用无量纲参变数表达形式,使其具有一定的普遍意义.按照这些曲线图或算式,结合实测悬链线的形态参数,便可推算出它的张力大小.     

降低单强变异系数 提高转杯纱质量的工艺探讨

单强变异系数是转杯纱评等的一项重要指标,可以通过调整一些工艺参数来降低转杯纱单强变异系数,从而提高转杯纱质量。     

改善苎麻及其混纺纱弹性研究

本文主要为了改善苎麻纱和麻棉纱的弹性,对苎麻纱、麻棉纱和棉纱进行了碱处理。并根据前人所做的工作,即有张力状态下碱处理和松弛状态下碱处理,其纱线性能存在较大差异,因而本文着重考虑在不同张力状态下进行碱处理,研究结果表明,采用低张力进行碱处理。其苎麻纱和麻棉纱的最大变形能力即断裂伸长显著增加,初始弹性模量显著下降,纱线变形恢复能力显著提高。     

转杯纱、环锭纱及其针织物性能研究

系统地对普梳和精梳转杯纱、普梳和精梳环锭纱等4种纱线及其相应针织物的各种性能,尤其是力学性能进行了比较系统的测试分析,并对其中某些性能的差异显著性作出分析检验。     

关于转杯纺纱曲线形态和张力的力学分析

本文讨论转杯纺纱(即气流纺)杯内纱的曲线形态和张力变化,从力学分析的角度来看,在有空气阻力并有足够大的阻捻盘作用下才能使纱形成稳定的正向剥取的曲线形态。如无空气阻力并无阻捻盘存在时,那就将形成反向剥取方式的曲线形态。否则是不能满足力学平衡和功能平衡的要求的。     

Configuration and Tension Variation in the Local Catenary Yarn Path

For the local catenary path of yarn in steady motion fre-quently encountered in textile processing,this paper studiesthe mathematical expression of its geometrical configurationand tension variation,as well as the curve inclination angleand its maximum suspending deflection.The final math-ematical equations and graphical curves are all presented indimensionless forms,as they are more general and universalthan dimensional expressions and graphs.On the otherhand,we can also find out the catenary yarn tension fromexperimentally measured geometrical parameters by calcula-tions based on these graphs or mathematical expressions asgiven in the paper.     

REPORT ON A PROJECT AIMED AT INCREASING THE STRENGTH OF FRICTION SPUN YARN BY USING A FALSE TWIST PROCESS

The lower strength of friction spun yarns has became a key problem that hinder the develop-ment of friction spinning,especially in high speeds and fine yarns.In this paper a project aimed atincreasing the strength of friction spun yarns by using a false twist process has been made.In re-ported experiment false twist was inserted into the yarn which has been formed on a friction spin-ning machine,so that it made the yarn untwist at first,then regain the twist.In the meantime draftwas applied to generate more tension than that which had been experienced during yarn formationon the friction spinning machine.It made the yarn reforming and the loosely bound fibres in thefriction spun yarn formed due to extremely low tension on the friction spinning machine becametighter.Results indicate that with the proper draft,tension and false twist the tenacity of processedyarn will increase more than 10%.This project is an attempt to discover whether improvements can be made and whether it isworth pursuing research into modifications of yarn structure.The results imply that if the yarntension can be raised during yarn formation on the friction spinning machine or a chance is offeredto the yarn to reform after the yarn formation the yarn tenacity will be increased obviously.     

A Study of the Behaviour of Denim Cloth Made from Modified Rotor Spun Yarn

This paper described the physical behaviour of three types of denim cloths produced from rotor yarn, ring yarn and modified rotor yarn (prepared by adding conventional twist to rotor yarn) respectively. Experimental work showed that denim cloth produced from the modified rotor yarn has superior properties over conventional rotor yarn in terms of surface texture and appearance,tearing strength and resistance to abrasion.     

环锭纺纱线气圈的研究

用圆柱坐标系建立纱线微段的微分方程,用数值方法求解可获得气圈形态及其纱线受力的精确解。用解析方法建立气圈形态及其纱线受力的近似解析表达式,可反映气圈各参数对形态或受力的影响,其分析过程清晰、简捷的特点显著。两种计算结果的相对误差甚微。