| The weft insertion mechanism is one of the most important components of rapier loom, whose function is to weft into the shed formed by the warp yarns, and weave into fabric required. The requirements of this process are more stringent, such as the fit time between opening and beating, steady accuracy, high-speed adaptability,product adaptability and so on. These factors directly affect the quality and production efficiency of fabric. There is still a large gap of loom manufacturing level between domestic and abroad. The factors must be considered is the transmission mode and transmission accuracy of weft insertion. The institutional clearance is caused by manufacturing, wear and assembly error, while each member are deforming in the high-speed movement, that will have certain effect to arrow’s impulse of rapier weft insertion rapier. Therefore, it is very necessary to study the influence of the mechanical parameters of the weft insertion on the performance of the loom, which is of great significance to improve the weft insertion and develop the textile machinery in the future.In this paper, Taking a certain type of rapier weft insertion as an example. The kinematics analysis, dynamic analysis and institutional accuracy analysis of spatial linkage weft insertion are carried out by the method of theoretical analysis and simulation software for 3D detection. The specific research work as follows:1) Based on the GTM type of rapier loom weft insertion, refining schematic diagram of mechanism, analyzing the working principle of mechanism. The motion function of the institution is deduced by theoretical calculation. Meanwhile, The 3D model is established by Pro/E according to the manufacturer’s 2D drawings. The motion simulation of the weft insertion is carried out based on the software’s institution analysis function, which verifies the weft insertion motion profile.2) The motion function characteristics of the members which are related to weft insertion are discussed. Focusing on analyzing the motion characteristics of the spatial linkage in the spherical 4R mechanism, and refining the influence of the institution’sstructural parameters on the spatial linkage. The results show that there is a trigonometric relationship between the structural parameters of spherical 4R mechanism and the spatial linkage, which is the main basis for the box and cross’ s structure design.3) Explore the DOF calculation method of the spherical 4R mechanism to solve the problem, that actual results can’t be obtained by ordinary DOF calculation method.The results prove that the DOF of the spherical 4R linkage weft insertion can be calculated by using the screw theory.4) The inertia load calculation method and load characteristics of the spatial linkage in the spherical 4R mechanism are discussed. The direct relationship between kinetic energy, equivalent inertia, inertia moment and input angle is established. The dynamic simulation of the weft insertion is carried out by using the 3D model established which has been imported into Adams. The bearing load of the spatial linkage is obtained, which is compared to verify the theoretical calculation.5) Under the premise of reasonable hypothesis, the accuracy of the mechanism is analyzed from the two aspects of kinematic pair clearance and structural deformation.Focusing on analyzing arrow’s impulse of kinematic pair clearance in the spherical 4R institution, and the deformation of key member by finite element simulation software Workbench. Synthesis investigating the effect of the transmission component on impulse. |
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