Radial Yarn Movement in Yarn Duct of Interlacer

In order to find the relations between the production performonce of interlacer and its cross-sectional Shapcs of yarn duct,radial yarnsd movement in varions yarn ducts of interlacer and its effect on performance of interlaced yarn were studied in this paper. Seven interlacers,which were diffcrent in the cross- sectional shape of yarn duct,were made. Yarn motion in yarn duct of interlace was observed with optical fibers and photo- sensors. Performance of the interlaced yarn was evaluated by the number and the strength of tangles. Experfmental results disclose the relations between the yarn motions and the properties of the interlaced yarn. The interlacer with round yarn duct is capable of producing an interlaced yarn with bigger number of tangles,since It can make yarn transverse frequently the axis of air jet issuing from air jet nozzle. The interlacer with cornered shape of yarn duct makes yarn subjected to the action of compressed air for a longer time,which results in larger strength of tangles.     

自动络筒机空气捻接器的捻接原理研究

研究自动络筒机空气捻接器的捻接原理.对退捻后纱线尾端的曲线函数进行研究,指出了一种合理的纱线尾端的曲线函数,并利用流体力学原理,具体描述了纱线在捻接孔内的运动,揭示了纱线捻接原理.     

Characterizing and Analyzing the Airflow Field inside the Nozzle Block of Murata Vortex Spinning

A three-dimensional computational fluid dynamics model is developed by software Fluent 6.2, to simulate the flow field inside the nozzle block of the Murata vortex spinning. The flowing state and the distribution law of static pressure and velocity are characterized and analyzed. The relationship between the flowing state and the structure of the vortex spun yarn is also discussed. The research results can enhance the understanding of the yarn formation principle from viewpoint of the airflow field law inside the nozzle block of Murata vortex spinning.     

喷气纺纱条动态气圈的转速与成纱强力的关系

喷气纺纱是利用旋转气流作用推动纱条形成气圈运动,使头端自由纤维加捻成纱。本文采用本组研制的纱条气圈转速仪对喷气纺纱纱条动态气圈的转速进行了测试,并就改变加捻成纱过程中的第一喷嘴和第二喷嘴的气圈转速,探讨其与成纱强力的关系。     

喷气纺喷嘴中气流场的分布规律

喷气纺纱中,喷嘴是决定成纱加捻包缠程度的关键,直接影响成纱质量,本文运用激光多普勒测速仪对喷气纺喷嘴中的气流场以及有关参数对喷嘴中气流场分布的影响作了测试分析,所得的结果对掌握喷气纺喷嘴中的气流场的分布规律、合理地设计喷嘴、优化有关参数等提供了依据。     

圆盘式旋流纺纱的工艺分析

介绍了圆盘式旋流纺纱的装置和流程，探讨了影响圆盘式旋流纺纱成纱性能的主要工艺参数，成功地纺制了包芯纱．为了解和掌握圆盘式旋流纺纱设备的纺纱性能、工艺特点，对所纺纱线的强度和耐磨性进行了测试．根据测试结果，分析了圆盘式旋流纺纱的主要工艺参数与成纱性能之间的关系，发现第一喷嘴压力、第二喷嘴压力、梳辊转速、喂棉量、棉条号数、喂入张力、芯纱退绕张力是圆盘式旋流纺纱的主要工艺参数．     

基于双向耦合作用流场中异形筘内纬纱运动稳定性分析

为研究影响柔性纬纱纤维束在异形筘内流场的运动稳定性的因素,解决高速引纬过程断纬问题。考虑气流-纬纱两相耦合作用,通过基于任意拉格朗日-欧拉法建立柔性纬纱-流场耦合控制方程、数值模拟的方法得到了异形筘槽内瞬态流场的分布及纬纱运动特性,并通过高速摄像系统获得纬纱在流场中的位移验证了数值结果的正确性;详细讨论了辅助喷嘴的出口形状及尺寸等参数对纬纱运动特性的影响,结果表明:星形孔辅助喷嘴射流能够快速进入异形筘道与主喷嘴射流汇合,主气流的核心区域最长,引纬速度高,纬纱运动稳定性最好;随着喷孔直径的增大,纤维头端的弯曲变形增大,纬纱运动稳定性变差。可见小直径星型孔更适于高效引纬。     

低弹网络丝在喷嘴丝道内运动规律探讨

本论文借助于实验手段揭示网络加工过程中,低弹丝在喷嘴丝道内受气流作用时的运动规律和气流在喷嘴丝道内的流动规律,借以揭示网络丝的网络结形成机理,为合理设计网络喷嘴提供依据。     

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。     

The Yarn Curve and Tension in Rotor Spinning

The effective way of finding the yarn curve shape and tension of OE（open end） yarn inside the rotor is carried out and treated by dividing the yarn curve into two parts, from which the trajectory of the yarn sliding on the navel surface is also obtained. It is pointed out that the yarn curve shape and tension will both fluctuate with the trajectory＇s revolving cycle inside the rotor. However, the fluctuation is not too great, so the motion can still be regarded as approximately steady for dynamic analysis.     

喷气纺喷嘴中气流流动的数值计算

采用2-D模型对喷气纺喷嘴中的气流流动进行数值计算，并与其他研究者的实验研究结果进行了分析比较。根据计算结果描述了喷嘴中气流流动特征，重点分析了参数对气流流动特征以及成纱性能的影响。     

单面羊毛衫添纱织物编织的研究

分析了垫纱横角和垫纱纵角对羊毛针织绒线在织物中显现情况的影响规律，推导出了横机纱线断面轨迹方程，通过上机确定了编织毛盖棉织物时较理想的垫纱角度．     

单面圆纬机纱线断面轨迹分析

在添纱双面效应针织物的编织过程中,旧线圈握持线为圆弧线,与传统理论中所描述的握持线为直线不同,因此对纱线的实际垫纱横角与垫纱纵角进行了设定.根据织针在成圈过程中沿弯纱三角下降的同时沿针筒圆弧进行回转的运动规律,推出针钩内点与纱线断点相对于针筒中心的运动参数方程,通过坐标转换得到纱线进入针钩内点的断面轨迹理论方程.进一步作出纱线断面轨迹曲线,分析了不同垫纱角度配置时形成织物的添纱效应.     

自动络筒机上毛羽减少装置的研究

介绍了一种自行研制的自动络筒机毛羽减少装置，并用涤棉纱和纯棉纱作了应用试验，试验结果表明：采用此装置后，纱线毛羽有明显的减少，尤以5mm最多，达70％左右。     

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。     

周转轮系差速器双轴送经的余纱长度分析

在阔幅织机上,以周转轮系差速器作双轴送经的方法可以通过机构自动调节来缩小两织轴的经纱张力差异。但是,机构本身的结构及其故障都会引起两织轴的余纱长度不等。以两套电子送经机构分别控制丙只织轴的送经运动,是克服余纱长度不等的措施。     

集聚纺的纱线强力理论

为了从理论上分析集聚纺纱线较环锭纺纱线强力提高的原因,基于两种纱线的结构差异,如纤维的转移、纤维的堆积密度、纱线的直径等,建立了一个纱线结构计算模型.从理论上分析了纤维伸长率分布、纤维堆积密度及纱线直径对纱线强力的影响,合理解释了集聚纺纱线强力上升的原因.     

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.     

紬丝包芯纺纱的探索

本文介绍了一般的包芯纱,包绕纱中纤维的组合形式、纺纱方法及成纱特点。在此基础上介绍了(纟由)丝包芯纺纱的工艺、试验所用的材料、成纱品质及其与(纟由)丝的比较。从而指出(纟由)丝包芯纱兼备了(纟由)丝和化纤长丝的特点。因此,(纟由)丝包芯纺纱有继续探索的必要和可能。     

纱线毛羽特征参数提取算法研究

提出了用于对纱线毛羽特征参数提取的多区域轮廓跟踪算法,该算法是在链码法轮廓跟踪算法的基础上,对跟踪方向进行调整,并对已跟踪完成的纱线区域进行区域填充.实验表明,该算法不但可以对任意条纱线进行轮廓跟踪及特征提取,而且得到的边界曲线封闭连续,只有单像素宽,提高了特征提取的效率和精度.