特殊压脚对缝纫工艺质量及效率的影响研究

研究并探讨了特殊压脚对提高服装缝纫工艺及效率的影响。通过对特殊压脚的缝纫工艺效果及实验织物厚度的观察和测定进行缝制效率研究,并计算了相关成本。研究结果表明:特殊压脚的缝纫工艺质量及效率优于普通压脚,除特殊情况外,其效率均能提高50%以上;不同材质的特殊拉链压脚缝纫工艺效果相似,对于多数织物塑料压脚工艺用时少于铁质压脚,且缝纫效率变化受到织物厚度的影响;合理使用特殊压脚可以减少时间成本和劳动力成本。     

电脑横机压脚毛刷连动系统的设计

针对目前电脑横机编织过程中容易出现压脚与毛刷共用空间位置重叠的现象,设计一种新型的压脚毛刷连动系统。在介绍常规压脚工作原理、毛刷主要作用和安装定位的基础上,分析压脚毛刷空间位置重叠产生的原因,并详细阐述压脚毛刷连动系统的设计思路、机构分析、工作原理以及安装调节螺钉的方法等。该连动系统的应用能够解决压脚与毛刷共用空间位置的重叠问题,实现织物的顺利编织,为电脑横机的结构优化提供参考。     

织物起拱残留高度的预测方法

织物起拱残留高度在测量中是动态变化的,这种变化又是微量的,人工静止测量容易产生较大的误差。为了提高织物起拱残留高度测量的可靠性和自动化程度,基于MatLab程序,利用图像处理技术,对从改进后的图像采集平台获取的织物起拱图像进行处理,通过动态阈值变换、欧氏距离算法等,计算得到未起拱织物与起拱织物之间的欧氏相对距离,经线性回归分析得到相应的实际织物起拱残留高度。实验和分析表明,采用该方法测量并计算出的织物起拱残留高度与实际测量值之间没有显著性差异,达到了所要求的测量精度。     

海德堡印刷机故障分析100例

1.印刷时,飞达纸堆不能自动上升 如图1所示,印刷时,当压纸脚压住纸堆,而纸堆低于一定高度时,压脚机构中的触角触动微动开关b92,通过电气系统,使纸堆上升一定距离.当纸堆达到一定高度时,压脚机构无法触动微动开关,纸堆不再上升.     

MFB-2600型双针三线绷缝机使用与调整（下）

3．12压脚的调节 3．12．1压脚压力的调节 因缝料的种类和厚度等条件不同，对压脚压力的要求也不相同。一般来讲，压脚压力以能顺利送出缝料最低限度的高度为最理想，想要调高压力时，顺时针转动调压螺钉①，反之要减小压力时，则逆时针转动调压螺钉①（图20）。     

无捻纱捻度设计及织物湿传递性能探讨

研究无捻纱的设计要点和无捻纱机织物的湿传递性能。采用捻幅理论模型分析了反向合股法生产无捻纱所需的股线捻度,并进行了验证。比较了无捻纱平纹棉机织物与有捻纱平纹棉机织物的外观、厚度、紧度、透湿量和芯吸高度。试验结果表明:当反向合股捻度等于棉单纱捻度时,股线退维后棉纱可呈现无捻状态;无捻纱机织物的厚度、紧度和透湿量较有捻纱机织物大,无捻纱机织物的芯吸高度大于有捻纱机织物,且织物的经向芯吸高度大于纬向芯吸高度。指出:直径相同的棉纱和PVA短纤纱采用反向合股技术生产无捻纱时,采用的股线捻度应等于棉纱捻度;纱线捻度对织物的透湿状态有一定影响。     

压脚编织技术

本文简单回顾了压脚的发展历史;着重介绍了压脚的工作原理;分析了压脚形状与针床截面形状对编织织物的影响;简单介绍了压脚的作用以及具有压脚机构的横机进行成形编织的典型方法。     

经编光纤传感织物结构变化对光纤弯曲损耗的影响

为研究经编光纤传感织物在纵向拉伸状态下织物结构变化对光纤弯曲损耗的影响,编织了一种以经平绒织物为地组织、聚合物光纤为衬纬纱的经编光纤传感织物。将光纤以半径为10 mm的半圆反向相接的形式织入地组织中间位置,形成传感单元。同时,测量了传感织物在拉伸条件下的线圈高度、线圈宽度和织物厚度;并测试了在织物拉伸回复状态下光纤信号的传输性能。结果表明:光纤可通过衬纬的形式与经编织物相结合;在拉伸过程中织物纱段发生转移,织物厚度随拉伸距离的增加而减小;纱线对光纤的挤压作用使光纤产生微弯损耗,且在拉伸过程中微弯和宏弯损耗相互复合。     

用恒温板测试织物透湿性能

采用恒温板测试法,测量了33℃和50℃条件下,不同紧度、不同材料、纳米粉体改性织物前后以及层压和聚四氟乙烯膜4组试样的透湿性能.结果表明,织物透湿量与测试时间呈高度线性相关;使用透湿速率指标可以区别织物的透湿性能.对于特殊规格织物,透湿速率随着容重的增加而增大,当容重为一定值时,透湿速率达到最大,之后,又会随着容重的增加而减小.材料对透湿性的影响比较复杂,测试温度不同,透湿速率就有所不同,温度越高,透湿速率相差越小.纳米粉体特性和处理试剂对透湿性能有影响.层压复合织物两面的透湿速率不同.当聚四氟乙烯膜厚度等参数相同时,透湿速率随单位面积中开孔面积的增加而增大.     

在国产横机上设计压脚装置

一、概述在国外,八十年代发展起来的压脚成形技术被誉为“八十年代新技术”。其特点在于压脚对织物起无张力的“牵拉”作用,因而使新的横机产品具有下列优点: 1.织物的外观、缩水问题得到改善; 2.手感柔软、线圈蓬松; 3.拷、放针的枚数可任意; 4.和选针机构相配合,可编织出更加     

水分沿针织物纵横向传递速度的研究

采用同一种棉纱织成6种同组织不同结构的针织物,运用水平芯吸的实验方法,分别测试水分沿针织物纵横向的芯吸速率,发现芯吸高度h与时间t可以很好地用h=atb表示.通过线性回归得出织物结构参数--纵密、横密、织物厚度对芯吸速率的影响,结果表明针织物的芯吸不能简单地用毛细上升的规律来描述.在织物结构参数影响中织物厚度的影响最大,织物越厚,芯吸速率越小;织物纵密、横密越小,芯吸也加快.此外,也对针织物的芯吸规律进行了一些探讨.     

Out-of-plane permeability of 3D woven fabrics for composite structures

Abstract

Polymer composites in structural applications commonly provide reinforcement based on 2D textile products, such as woven fabrics or non-crimp fabrics. This leads to sensitivity for delamination and high lay-up effort, especially when a large part thickness is required. 3D woven fabrics (3D-WF) can prevent delamination by incorporating fibers in out-of-plane direction and given the increased areal weight of the single layers, the effort for lay-up is strongly reduced. However, large part thicknesses are also challenging when it comes to impregnation. A high out-of-plane permeability helps facing this challenge. Within this study, the saturated out-of-plane permeability of different 3D-WF (glass fiber) with an areal weight ranging from 1850?g/m² to 5242?g/m² was measured. It was found that at an equal fiber volume content of 50% the increase of out-of-plane oriented reinforcement fibers leads to an increasing out-of-plane permeability with increasing areal weight.     

Cut resistance of hybrid para-aramid fabrics for protective gloves

This paper deals with cut resistance of hybrid woven para-aramid fabrics tested according to the appropriate clause of EN 388 – “Protective Gloves against Mechanical Risks”. Abrasion, puncture and tear resistance properties of the fabrics were also measured. The experimental sample set was plain-woven fabrics made of hybrid yarns composed of staple para-aramid fibres with different core/sheath ratios of various filaments in their structure. The effects of core/sheath ratio and core filament type were investigated. The results revealed that decreasing core–sheath ratio of the hybrid yarns led to the increase in weight and thickness, resulting in improved cut, abrasion and puncture resistance properties. It was confirmed that cut resistance increased with the increase in thickness and weight of the fabric. Para-aramid/Dyneema® fabric had higher cut, abrasion and puncture resistance properties.     

荡领造型的影响因素分析

采用5种性能不同的面料,分别测量出它们的厚度、悬垂性、面密度、抗弯刚度等物理性能.在结构设计中以剪开量的不同为参考因素,用不同面料制作连身肩部无褶的荡领,并对其进行褶皱测量.根据面料性能、剪开量及褶皱测量的数据,分析面料的性能和结构参数对荡领造型的影响.结果显示:荡领的褶皱造型与剪开量有密切关系;同种面料,荡领褶皱的数...     

The effect of knit structures with tuck stitches on fabric properties and pilling resistance

The patterns of knit fabrics are designed by loops, tuck stitches, and float stitches and their combinations. The tuck stitch has important influences on fabric properties. It increases the fabric’s weight, thickness, and width and makes the fabric more porous than other fabrics. In this study, to determine the effects of knit structures which are made from the same cotton yarn with tuck stitches on fabric properties and pilling resistance, circular knit fabrics with different locations and number of tuck stitches were produced and dyed under the same conditions. In the evaluation process of the results, graphs were drawn and variance analyses were performed. At the end of the study, important findings were determined. The number and location of the tuck stitches and stitch length are effective factors on the structural, physical properties and the pilling resistance of knit fabrics. The fabrics with tuck stitches have much higher porosity, weight, and thickness compared to single jersey fabric. The dyeing process increases fabric weight. Single jersey has the lowest pilling resistance in comparison to fabrics having tuck stitches. The fabrics having more pores and larger pores show higher resistance to pilling. Dyeing and finishing processes decreased the pilling resistance of fabrics.     

The Beneficial Influence of Enzymatic Scouring on Cotton Properties

Abstract

Enzymatic scouring has been investigated for over two decades as an environmentally friendly process. Replacement of harsh alkalis by enzymes minimizes not only the COD and BOD in effluents, but also the amount of effluents, because the rinsing step may be omitted. However, advantages of enzymatic scouring on treated fabrics should also be highlighted. The benefits provided by enzymatic scouring are introduced in this paper. Enzymatic scouring was conducted under optimized conditions established previously. The weight loss, damage to fiber surface, softness, and pilling tendency of enzymatically treated fabrics were measured and compared with alkali scoured fabrics. Furthermore, K/S values of the scoured and dyed fabrics were measured before and after a number of washes in order to investigate the effect of residual enzymes on dye-ability and colorfastness.     

Modeling the bagging behavior of worsted fabrics using response surface methodology

In this paper, we have studied the effect of a number of loading cycles on fabrics bagging behavior, and then investigated the influence of factors such as sample weight, test speed, and sphere diameter on the worsted fabrics bagging behavior using response surface method (RSM). Six worsted fabric types with different weights were prepared and then the bagging properties of these fabrics were measured using a newly developed test method. Bagging parameters including bagging force, work, fatigue, resistance, hysteresis, and residual height are calculated. Then, a statistical model (RSM) was used for the experimental plan (with these factors) to determine the runs of an experiment (or selected points). The experimental results showed that sample weight and sphere diameter have a significant effect while test speed has no significant effect on the bagging parameters. Also, the fitted models of bagging parameters are obtained and coefficient effects are estimated.     

A study on thermal properties of single-jersey knitted fabrics produced from ring and compact folded yarns

This paper presents a study on the thermal properties of single-jersey knitted fabrics manufactured using ring, compact and ring/compact folded yarns. The variations in thermal properties depending on the yarn twist and traveller weight of folded yarn single-jersey knits were discussed. It was found that the thermal resistance of knitted fabrics generally increases as the traveller weight decreases, and also water vapour permeability reduces as the traveller weight decreases. The water vapour permeability and air permeability of knitted fabrics increase as the twist increases. The thermal conductivity of knitted fabrics decreases as the twist increases. The air permeability and water vapour permeability values were higher for compact folded yarn fabrics as compared to those values of ring and ring/compact folded yarn fabrics. It is observed that yarn twist and traveller weight have affected different thermal properties of single-jersey folded yarn fabrics.     

Modeling of thermal properties of multilayered fabrics by ANN consisting of polypropylene needle-punched nonwovens

This paper presents the prediction of thermal and evaporative resistances of multilayered fabrics meant for cold weather conditions using artificial neural network (ANN) model. Thermal and evaporative resistances of fabrics were evaluated using sweating guarded hot plate method. The significance and interdependency of thickness on other fabric and process parameters and its effect on prediction performance of ANN model is analyzed in detail. For this purpose, two different network architectures were used to predict the thermal properties of multilayered fabrics. In both the networks, three-layer structure consisting of input, hidden and output layers was used. First, network was constructed with four input parameters, namely linear density of fiber, mass per unit area, punch density, and thickness of nonwoven fabric which predicts thermal and evaporative resistances. Second network was made with three input parameters, namely linear density, mass per unit area, and punch density. The network parameters were optimized to give minimum mean square error (MSE), mean absolute error percentage, and good correlation coefficient. The trend analysis was conducted and influence of various input parameters on the thermal properties of multilayered fabrics was studied. The significance of each input parameter in the prediction of thermal properties was studied by carrying out sensitivity analysis. The mean square error of the test dataset before and after the exclusion of the corresponding input parameter is taken for analysis. The input parameters were ranked based on the MSE ratio of test dataset. The predicted thermal properties of multilayered fabrics are correlated well with the experimental values. It was observed that the ANN model with minimum input parameters, namely linear density of fiber, mass per unit area, and punch density can predict the thermal properties of multilayered fabrics with good accuracy.     

63—THE EFFECT OF FABRIC PARAMETERS ON SOUND-TRANSMISSION LOSS

The dependence of acoustic-transmission loss on the weight, thickness, and cover of woven fabrics is investigated over a broad range of frequencies. In actual fabrics, these variables are seldom independent of each other, so that their composite effect, in which cover has been shown to predominate, must be considered. In simulated models, in which these parameters are isolated, fabric weight and cover are shown theoretically to have a direct influence on transmission loss, whereas thickness appears to influence sound reduction inversely. These effects are especially evident at higher frequencies.