Instrument for Measuring the Appearance Width of Running Double Ply Staple Yarn Using Lightness Threshold for Yarn Image

Abstract

The yarn thickness has been defined in the relationship between length and weight of the yarn. However, the appearance width (diameter) of the yarn plays an important role in the dimension of knit wear products. In addition, the appearance width is related with final twist number and affects yarn properties. In this study, a measuring instrument of the appearance width of running double ply staple yarn with yarn tension control is developed. The image of the yarn can be obtained with a CCD camera and a flat type LED panel with brightness control. A method to exploit a certain threshold to divide the core and fluff in the image of the running double ply staple yarn is introduced. Experimental results show the validness of the obtaining appearance width.