Multiple weft yarns are arranged in shuttles at different heights during the formation of three-dimensional carbon fiber fabrics.To ensure that each layer of weft yarns can withstand a uniform beating-up force,the reed must move horizontally in the front dead center,simultaneously feeding each layer of weft yarn into the weaving mouth.Traditional beating-up methods,such as linkage and conjugate cam mechanisms,cannot meet the requirements of multi-layer three-dimensional fabric weaving technology because they can only achieve circular arc trajectory movement of the reed.To solve the problem of uniform force on each layer of weft yarns in three-dimensional fabrics,this paper proposed a parallel beating-up mechanism composed of a conjugate cam and a planar linkage.In this paper,through an analysis of the form and mechanism principle of beating-up,a modified trapezoidal acceleration motion law was applied to the parallel beating-up of a reed.A reverse design program was compiled in the Matlab environment for the swing arm motion law and the conjugate cam theoretical profile.The Step function was used to simulate the beating-up resistance caused by multi-layer three-dimensional fabrics,and a functional prototype simulation model of the parallel beating-up system was constructed by Adams/View software.The kinematic and dynamic performance of the system were simulated and analyzed,taking into account factors such as beating-up resistance,contact collision,and conjugate clearance.A parallel beating-up mechanism suitable for multi-layer three-dimensional fabrics was developed by effectively connecting conjugate cam and planar linkages through mechanism combination.A calculation method and simulation idea for the beating-up resistance of multi-layer three-dimensional fabrics were also proposed.It is found that near the front dead center,the angular acceleration of the rocker shaft reaches its maximum,and the reed undergoes stable horizontal motion along the X direction,which can well meet the requirements of parallel beating-up technology.Due to conjugate clearance,high-frequency collisions between the main and auxiliary cams and rollers can cause mechanical vibration,adversely affecting the dynamic accuracy of parallel beating-up.The new beating-up mechanism has good process applicability and practical application prospects.It provides technical ideas for the design innovation of parallel beating-up for multi-layer three-dimensional fabrics made of carbon fibers.
维普
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