Conventional 2D loom

The shedding mechanism is one of the primary motions of a loom. A Jacquard shedding mechanism is used for weaving 3D preforms because the individual warp fibers are controlled independently by Jacquard harness cords. A 3D fabric and preforms can be woven on a 2D conventional rapier loom, but there is a fabric thickness limitation when using any conventional 2D loom. 

The 3D preforms on a conventional 2D loom are woven in a flat form. The first step in weaving 3D preforms on a conventional 2D loom is to figure out how to flatten (Greenwood et al., 1992) the stmcture. Once it is determined, it is followed by the subsequent setup of the loom and the weave architecture. The filling path, based on the performance requirements of 3D preforms, has to be carefully selected. Figure 9.59 shows weaving of carbon-tapered Pi structures in a narrow fabric shuttle loom. 

D multilayer woven fabrics made on conventional 2D weaving looms are commonly distinguished as warp interlock and weft interlock these two subcategories have certain similarities but also possess substantial differences. Warp interlock 3D woven fabrics were introduced much earlier than the weft interlock ones (see inventions in... 

This t q)e of fabric preforms can be produced either on the specialty weaving machines or (in limited thicknesses) on conventional 2D weaving looms both these machine types are fully automated and have been already used for industrial-scale fabric production. 

Plain woven 2D fabric reinforcements were manufactured on a conventional weaving loom. Glass tows were used in warp and weft. Reinforcement characteristics have been summarized in Table 14.2. 

The 2D conventional loom is modified to weave various 3D woven preforms. What kind of modification(s) should be carried out depends on the nature of preforms to be produced. The take-up and shedding motions are modified in many ways along with other tools that are also installed. Modified looms are used to produce thick panels, contour materials, polar materials, and complex 3D preforms. An unlimited number of 3D preforms and complex shapes can be woven on a modified loom with electronic Jacquard. Figure 9.60 shows a narrow fabric shuttle loom weaving a 50-mm-thick carbon panel. An orthogonal weave has been used with a dead pick motion so thatX, Y, and Z fibers are perpendicular to each other. 

There are two different approaches in the development of 3D textile structures one is the use of conventional weaving techniques developed for the production of 2D fabrics. They have been successful in manufacturing different types of 3D fabrics (Sun et al., 2013 Chen et al., 2008). The conventional looms are mainly designed for production of 2D fabrics for domestic applications. Although they have been used for making 3D fabric with various types of structures, they would face problems when the thickness of the 3D fabric becomes substantial. In addition, the conventional looms only allow the weft yams to be inserted in one direction this would limit the scope of the creation of 3D architecture (Chen et al., 2011a Figure 13.6). 

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