*4.2.3.2. By rotary braiding*

in the machine bed. Each individual row has a braider carrier in order to carry out four different

Brown developed a 3D circular braided fabric having one set of fiber sets [90]. In order to form the fabric structure, these fiber sets are intertwined with each other. The machine has concentric rings that are attached to a joint axis. Braid carriers are circumferentially mounted to the inside diameter of the ring. The ring is adjusted depending upon the thickness of the fabric. The rings rotate one braid carrier distance depending on a pre-determined path. Then, the braid carriers move in the axial direction. After that, the cycles are repeated in the above sequence. The fabric has ±bias yarn orientation through the thickness of the cylinder wall and cylinder surface at

**Figure 30.** Schematic views of (a) 3D braiding machine and (b) yarn carrier path [69].

**Figure 31.** (a) Schematic views of 3D circular braiding machine [90] (b) yarn carrier path [69].

cartesian motions (Figure 30).

106 Non-woven Fabrics

the helical path, as shown in Figure 31.

This method is essentially a derivative of the maypole braiding. In 3D rotary braiding braider carrier can move freely and arbitrarily over a base plate. Hence, each braider yarn can be interlaced into the fabric [9, 91]. Tsuzuki developed a 3D braider that contains star-shaped rotors arranged in a matrix of multiple rows and columns [92]. Each rotor is surrounded by four carriers that are able to move in four diagonal directions. The directions in which the carriers move are governed by the rotation of the rotors (Figure 32).

**Figure 32.** Schematic views of (a) 3D rotary braiding machine and (b) yarn carrier actuation unit [92].
