The Backrest roller is one of the key parts of the weaving machine. In this study, the effect of the various position of backrest and dropper has been assessed. The tension is measured by using the integrated tension measuring device of the loom. The tension can be found on the display board. The effect of backrest position can be described in two different ways viz. keeping constant dropper position (distance between dropper line and backrest roller) and keeping constant dropper depth (distance between held frame and dropper line). If dropper position (distance between backrest roller to dropper line) is kept constant then the backward movement of backrest roller will entail low tension. The reason behind this is, the dropper weight will be moved toward the backrest roller and will lose its influence on warp tension. But if dropper depth is kept constant (i,e dropper line is kept intact) then the backward movement of backrest will require more tension as the influence of dropper will more on warp length. On the other hand, when backrest height is lowered then, the downward movement of backrest roller will need low tension and upward movement of backrest roller will need more tension. As the warp length and lap angle increases with the backrest height. In this paper, the whole phenomenon is explained with illustration.
IntroductionWeaving is one of the most important fabric manufacturing processes. For producing good quality fabric proper warp tension is a vital need. High tension may cause high warp breakage and low tension can cause different fabric faults. For ensuring proper warp tension electronic warp control (EWC) is used in the modern loom. But changing of different loom setting points can play an important role in determining proper warp tension which may be an important tool for eliminating starting mark, weaving damage, frequent false stoppage etc.The backrest is one of the most crucial parts of loom setting. It affects the fabric properties and quality. Fabric appearances, dimensional stability, starting mark, tensile strength etc are directly related with backrest roller position. H. Tahakori Shad et. al. (H. Tahakori Shad, 2013) found that the position of backrest roller has significant effect on breaking strength, elongation at break; tear resistance, abrasion resistance, air and water permeability etc. on grey fabric along the warp but it has no significant influence on the breaking strength in the weft direction, weft yarn density, abrasion resistance, and fabric weight. To have different backrest oscillations, springs with different stiffness were used. For each spring, fabrics with various weft densities were woven, and the warp tensions were measured and saved during the weaving process. Kloppels M et. al. (Kloppels M, 2002) reported that the variations in warp yarn tension during the weaving process become smaller by the backrest roller's swinging motion. At a high speed of the weaving machine, it could be possible to obtain a suitable relationship between movements of the backrest ...