Research On Working Devices Optimal Design For Flat-wrecker

Wreckers used for roadside assistance,illegal vehicles handling and other work content often appear in our life,well known to people.With the rapid growth of China's highway mileage of different grades and the increase of car ownership year by year,coupled with natural disasters and extreme weather in recent years,the demand for wrecker has been increasing,and the higher requirements on the performance of wrecker have been put forward.There is a big gap between domestic and foreign development in wreckers.In order to meet the market demand,improve the efficiency of wrecker,raise the level of energy saving and environmental protection,the performance of the wrecker's working devices needs to be promoted.Therefore,it is very important to study the optimization design of wrecker working devices.The research was based on a certain flat-wrecker which was cooperatively designed by a special purpose vehicle manufacturing company and Hebei University of Technology.The following work was done: The working devices and Class II chassis three-dimensional model were established.The multi-body dynamics model of the flat-wrecker was established to simulate the working state of the pallet assembly and the trailer arm assembly.It was verified that the structural design met the functional requirements.The hydraulic cylinder force situation was obtained.The cable system of flat-wrecker was established and the dynamic simulation of the traction condition was carried out,and the elastic vibration of the cable was simulated accurately.The stress curve of the pulley and the winch was obtained.The stress curves of pulleys,winches and other mechanical were obtained,which provided the data for the finite element analysis.The finite element models including working device,slide assembly and main frame were established.The strength and stiffness of working devices under full load bending and full load braking condition and the frequency analysis of working devices in free mode were carried out,with the outside excitation frequency range avoided effectively.Topology optimization and size optimization of the tray assembly and arm assembly were done,and it was verified that the new working devices satisfied the design requirements after lighting the weight of 239.37 kg.The optimization design about the flat-wrecker had achieved good results.