| Since the appearance of the first three-wheeled vehicle in the world,the automobile industry has developed more than 100 years.Since the 21 st century,both production and ownership of automobiles have reached new highs.And car safety has always been one of the three important themes of car development.Due to the late start of China’s research on automobile safety performance,the current technology is generally backward,especially as the seat belt assembly as the core device in automobile safety systems,and its core technology is relatively lacking.Therefore,the research on the dynamics of automobile seat belt locking mechanism and the design of key components is of great significance to the development of seat belts.Analyze the working principle of the belt-induction system,establish an equivalent mechanical model of the belt-induction system,analyze the relationship between the external ratcheting disc,the inertial block and the sensitive pawl,and establish the dynamic equation of the locking mechanism.The numerical fitting method is used to improve the accuracy of the dynamic model.Perform parameter sensitivity analysis of the belt-induction system,analyze the effects of the inertia mass moment of inertia,the stiffness of the belt-sensitive spring,and the amount of spring pre-compression on the system lock-up acceleration and the amount of webbing pull-out,and use MATLAB to draw the relationship curve,determine the design range of core parameter of belt-induction mechanism.The mechanism of the belt-induction system was optimized,and the feasibility of the optimization was verified by Adams simulation.Analyze the working principle of the vehicle-induction system,and establish the equivalent mechanical model of the vehicle-induction system locking performance on different cases.Determine the relationship between the components.Establish the deceleration and locking mechanics equation of the vehicle-induction system and the solution is obtained to obtain the deceleration expression.The case data are substituted into the theoretical calculation models in two different cases,and the effects of the quality of the lever and the friction force on the deceleration and locking performance of the vehicle-induction system are compared and analyzed.Determine the reasonable design range of the inclination angle θ.The gap between the shaft and the hole of the ball housing is substituted into the theoretical calculation model to analyze the effect of the gap between the shaft and the hole on the deceleration.The accuracy of the theoretical calculation model was verified by Adams simulation analysis.Analyze the main failure forms and causes of the belt retractor reel and frame,use ANSYS workbench to analyze the structural strength of the retractor frame and reel,use the stress cloud map and deformation cloud map of the model and 3D design software to analyze the reel and the frame structural optimization design.The feasibility of the optimization was verified by ANSYS simulation.The locking performance of the belt-induction system was tested,and the pull-out acceleration and the pulling-out time curve of the webbing were obtained.The experimental results were compared with the theoretical calculations to verify the accuracy of the dynamic model of the belt-induction system.Finally,the tensile strength experiments of the retractor reel is carried out,the production samples of the new reel structure are tested,and a set of experimental fixtures is designed to ensure the scientificity and accuracy of the experimental results. |
