基于投梭压力角余弦耦合系数的引纬机构分析与优化OA

To address the long-standing issues of high impact,high wear,and the difficulty in achieving both high energy transfer efficiency and high impact strength in the weft insertion mechanism of shuttle looms,this study innovatively proposed a dimensionless parameter—the cosine coupling coefficient C of the shuttle insertion pressure angle. This study first established a dynamic analytical model with coefficient C as the core variable based on the classical impact theory,by equating the oblique impact between the shuttle rotor and the shuttle nose to a two-mass collision model concentrated at the contact point.Through theoretical derivation,explicit expressions for the impact impulse ∫Pdt,post-impact velocities u1 and u2,effective impact force component Pe,and kinetic energy transfer efficiency η were obtained.The model parameters were derived from the precise measurement of a 1515K-135 type shuttle loom weft insertion mechanism used for denim weaving,with the measurement conducted using a RoyalArm RA325 portable three-coordinate measuring arm to ensure the geometric accuracy of the model.Based on the derived explicit expressions,the regulation law of coefficient C on the performance of the weft insertion mechanism was revealed through numerical analysis:(1)in terms of impact load,the effective impact force component Pc monotonically increases with the increase of C value,indicating that a higher C value intensifies the impact;(2)as for motion performance,the velocity u2 transferred to the shuttle nose shows good kinetic energy transfer efficiency around C=0.889,while the rebound velocity u1 of the shuttle rotor decreases with the increase of C,which is beneficial for smooth operation;(3)with regard to energy efficiency,the kinetic energy transfer efficiency ηmonotonically decreases with the increase of C value,indicating that high impact load and high transfer efficiency cannot be achieved simultaneously. To verify the correctness of the theoretical model,a rigid-flexible coupling multi-body dynamics simulation model was established in the ADAMS software.Simulations were conducted under three center shaft rotation speeds of 125,150,and 175 r/min,and the impact impulse and shuttle rod angular velocity response data were extracted from the simulation results for quantitative comparison with theoretical predictions.The results showed that the relative error between the theoretical value of the impact impulse and the average value of the simulation was within 15％;the error between the theoretical prediction of the peak angular velocity of the shuttle rod and the simulation result was less than 7％.These results verified the reliability and engineering applicability of the theoretical model from the perspectives of momentum transfer and motion response. Through theoretical modeling and simulation verification,this study,for the first time,integrated the geometric effects of the two independent pressure angles of the shuttle rotor and the shuttle nose into a unified parameter C,and quantitatively revealed its regulation mechanism on the impact dynamics of the weft insertion mechanism.The research conclusion indicates that coefficient C is an important design parameter.In practical engineering optimization,there is no need to precisely pursue the extreme value of C,but rather to make trade-offs within the range of C less than a certain extreme value point(in this model,C＜0.889)based on different emphases on low impact,high efficiency,or low rebound.This provides theoretical guidance and parameterized design paths for achieving multi-objective optimization of the performance of the weft insertion mechanism in shuttle looms.