Study On Optimization Design Of Working Mechanism Of Wrecker

Wrecker is a kind of special vehicles with road rescue equipment that can crane and tow stoppage or accident vehicles and quickly leave the scene of the accident. With China’s highway mileage and car ownership continuous growth, the demand for wrecker increases rapidly. In order to cope with increasing complex road conditions and poor operating conditions, wrecker develops toward trend of heavy, multi-functional and intelligent.Firstly, the development of wrecker at home and abroad is introduced, and the development trend of wrecker in the future is summarized. The wrecker is classified and each kind is described in detail. Taken the design and developed HPD5250 TQZ wrecker as research object, the main components of this type of wrecker are listed. Using three-axis automobile axle load calculation method, wrecker’s axle load is calculated considering elastic tires and suspension of the wrecker.The 3-D model of whole car structure is established by utilizing of UG, both boom and corbel’s finite element model are established by using Hypermesh. The dangerous conditions are ensured and the finite element models are loaded respectively which combined with actual stress condition, then static FEA are made on the structure of them.Based on the stress nephogram and displacement nephogram which are obtained when boom and corbel were stressed in each case, the calculation results are analyzed in detail,and stress regional concertration are fund out and improvement suggestions are provided.In addition, natural frequencies and vibration mode of boom and corbel are obtained in the modal analysis, and the responses are studied for load swing incentive frequency, different road incentive frequency and engine excitation incentive frequency. Finally, utilizing the size optimization method which based on FEA, for each section of the corbel’s wall thickness do the parameter modeling and optimization, taking the mass as optimal object,corbel’s mass reduces 5.23% after the optimization. The optimization result proves that the displacement of corbel becomes little bigger, the stress distribution is more equality, and modal properties are improved, which provides a basis for production of the wrecker.