Design Of Transmission System Of Emergency Rescue Vehicle Applied In Narrow Terrain

Emergency rescue vehicles are a type of special vehicles in field working circumstance that respond to emergencies,such as natural disasters and man-made disasters.At present,rescue vehicles used in our country are mainly medium-duty and heavy-duty,which have large size and poor mobility,making it difficult to drive into narrow and complicated streets and roadways.Therefore,developing a rescue vehicle suitable for narrow areas and complex terrain has become the primary task of emergency rescue vehicles.This paper designs the structure of its dual-parallel-axis four-output transmission system for the performance parameters of fire rescue vehicles in a narrow area,simulates the dynamics of the entire vehicle,conducts the transmission system principle test and the complete vehicle test.The research contents are as follows:(1)The performance parameters of rescue vehicle in a small area determined,and design a two-parallel shaft four-output transmission system.According to the structure scheme of the rescue vehicle and the characteristics of the rescue site,the size parameters,quality parameters and performance parameters are determined.According to the parameter requirements of the vehicle,the dual-parallel shaft four-output transmission system which is easy to carry out pivot steering is put forward and its pivot steering process and transmission principle are analyzed.(2)H-type transmission system structure is designed.According to the design parameters of rescue vehicle,the power transmission parts such as engine,tire and gearbox are selected,and the structural design and strength analysis of the key transmission parts such as commutator,central drive axle and corner drive box are carried out.(3)The extreme working angle of the transmission shaft is tested,meanwhile,its dynamic characteristics under large-angle working conditions are also analyzed.According to the actual relative position of components of double parallel shaft four output chassis transmission system.Build a test bench for the experiment of the working angle of the transmission shaft,and then,measure the extreme working angle and posture of the transmission shaft.Afterwards,analyze the dynamic characteristics of the transmission shaft by using ADAMS.Finally,according to the analysis result,judge the working condition of each differential in the transmission system.(4)Analyzed the power performance and economy of the rescue vehicle and achieve the spin turning function test.A model of a H-type transmission system was built by using AVL CRUISE,and then,simulate analysis of various performance evaluation indicators,including dynamic performance and economic simulation.After the rescue vehicle chassis is assembled,checking whether there is interference when the drive shaft moves at a large angle,and carrying out pivot steering test.After all,it is verified that the transmission system structure of the rescue vehicle can support the vehicle to complete the pivot steering function.