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In order to reduce the labor intensity of workers and achieve the automatic holding and placing of fiber bales for reciprocating automatic bale plucker, the structure of an AGV-based holding cart of the belt and packaging bag automatic removal machine for fiber bales was introduced. The holding device of the cart was designed. The dimensions of the holding gripper of the holding device were determined. The main mechanisms and parts of the holding device and its supporting part were designed and calculated. According to the working requirements, the parameters of the rack and pinion of the drive mechanism of the holding gripper were designed. The load of each oil cylinder was determined and the selection of the oil cylinder were performed by carrying out force analysis of the fiber bale and each component. Based on the design, the height of the holding gripper was 1 200 mm, and length of the holding gripper was 600 mm. The opening and closing range of the gripper was 660 mm to 910 mm. The working pressure of the oil cylinder of the gripper was 140 kg/cm². The diameter of the oil cylinder was 100 mm, and the stroke was 5 mm to 280 mm. The minimum working pressure of oil cylinder of the supporting machanism of the gripper was 0.97 MPa. The oil cylinder diameter was 80 mm, the rod diameter was 40 mm and the stroke was 400 mm. [ABSTRACT FROM AUTHOR]

Swirling airflow plays a key role in textile production processes. The structure and properties of a textile processed by utilizing swirling airflow depend to a large extent on the dynamics of the fibers in the flow. This work presents a numerical investigation of the dynamics of a flexible fiber in the tangentially injected swirling airflow in a nozzle containing cylindrical and divergent conical sections, which is frequently encountered during textile production. Simulation of the three-dimensional, transient, compressible and turbulent swirling airflow field in the nozzle is first conducted. A model for the particle-level simulation of a flexible fiber in a wall-bounded flow is consequently adopted for studying the fiber motion in the nozzle. This model assumes the fiber to be composed of several massless elastic rods connected by rigid ball–socket joints where various forces and torques are exerted. The stretching, bending and twisting deformations of the fiber as well as the fiber–wall collision can all be modeled. The motional characteristics of the flexible fiber can be obtained by solving the translational and rotational equations for all the ball–socket joints in the fiber model. Based on the model, the effects of two process and nozzle geometric parameters – the nozzle pressure and radial position of the injectors – on the fiber motion are studied. The results show that the model and methods presented in this work can provide effective and useful insights into the dynamics of flexible fiber in the swirling airflow field inside complex-structured nozzles employed in the textile production processes. [ABSTRACT FROM AUTHOR]

Fiber-shaped sensors have great potential for real-time monitoring of human physiological signals thanks to the merging of electronic and textile technologies. This work reports on the fabrication of a core–sheath structured strain-sensing fiber based on the wet-spinning method. The sensing fiber is composed of a core of non-conducting polyurethane and a conducting sheath of carbon black in a polyurethane matrix. Microscopic observation reveals the irregular shape or scattered appearance of the core as well as the porous structure of the fiber, the diameter of which is in the range 200–500 μm. The electro-mechanical properties and their dependence on carbon black concentration in the sheath and draw ratio between the spinneret and first drafting roller are experimentally investigated. It has been found that the percolation threshold of the fiber is in the range 15–16 wt%. The resistance of the fiber rises stably as the fiber is stretched up to a strain of 120% and increases with the increase of draw ratio between the spinneret and first drafting roller. In the cyclic tensile tests, the resistance of the fiber exhibits good repeatability in subsequent loading–unloading cycles after pre-stretching, despite partial recovery of the resistance in the first few cycles. The integration of the strain-sensing fiber into textiles is demonstrated by the core-spun yarn fabricated based on a modified vortex spinning method. The results of this study indicate the fiber could be a promising candidate for a sensor for smart textiles. [ABSTRACT FROM AUTHOR]

Airflow has wide and important applications in textile manufacturing. The dynamic behavior of fibers in the airflow can have a decisive influence on the structure and performance of the resultant textiles. In this paper, a three-dimensional model for the particle-level simulation of the dynamic behavior of multiple flexible fibers in a wall-bounded fluid flow of finite Reynolds number is proposed. The fiber is modeled as made up of a series of massless elastic rods connected by rigid ball-socket joints. In the model, both the internal and fluid forces and torques are applied on the ball-socket joints while the elastic rods only serve to transmit the internal forces and maintain the connectivity of the fiber without interacting with the ambient fluid. Each pair of adjacent elastic rods can bend and twist at the ball-socket joint connecting them, thus the stretching, bending and twisting deformations of the fiber can all be modeled. The motions of the fibers are governed by the translational and rotational equations for each ball-socket joint and both the fiber–fiber and fiber–wall interactions can be solved based on the hard sphere model. Using the proposed model, the regimes of the motion of a threadlike particle in a shear flow and the interaction of a single rigid fiber with a solid wall in Poiseuille flow are successfully reproduced, which agrees with the experimental results found in literature. The model is applied to the simulation of the motions of multiple flexible fibers in the airflow field inside the fiber transfer channel of the rotor spinning machine. Based on the simulation, the motional characteristics of the fibers as well as the effect of the transfer channel on the straightness and parallelization of the fibers are analyzed. The results indicate that the model proposed in this paper can provide an effective means of studying the dynamic behavior of the flexible fibers in the flow field involved in the textile production processes and a promising way of optimizing the design of the key components of textile machines. [ABSTRACT FROM AUTHOR]

A numerical model is presented to simulate the fiber motion in the airflow inside the vortex spinning nozzle (VSN). The coupling between the fiber and airflow together with the fiber-wall contact is solved. Based on the numerical model, the motional characteristics of four types of fibers-cotton, viscose rayon, lyocell, and polyester fibers-in the airflow inside the vortex spinning nozzle are simulated and analyzed. The vortex yarn structure is viewed under the scanning electron microscope and the fiber strength utilization factors of the vortex yarns spun from different types of fibers are compared to verify the wrapping effects of different types of fibers in the vortex yarns obtained by the numerical simulation. The agreement between the numerical and experimental results shows that the numerical modeling methodology proposed in this research provides a reliable way of investigating the fiber dynamics in airflow and an efficient solution to the mechanical problems in polymer/textile manufacturing processes involving fluid-solid coupling. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]