Research On Design Of Signgle-Axle Driving Bogie

The urban mass transit system has many characteristics such as high efficiency of transportation, high-speed, punctuality, economizing energy and space, high security and protecting environment, so it has gained favor of many cities in the world. To solve the traffic problems in developing of cities, the basic way is to establish a modern integrated traffic system based on the railway trasit such as metro, light railway, monorail transit etc.As the direct transport tools in the urban mass transit system, vehicles have to fit into the environment of each city. nd the bogie is one of the major components of a vehicle, it transfer each forces, and produce tractive force using adhesion force between wheel and rail. The performance criteria of a bogie determine directly the tractive effort, running quality, wheel-rail wear indices and security of the train.The single-axle driving bogie is composed of a wheelset, frame, driving mechanism, brake rigging and suspension components. The major difference between single-axle bogie and general two-axle bogie is that single-axle bogie has only one wheelset, and it needs a suit of balance device to restrain pitching vibration of its frame.This thesis is to introduce the development and status of single-axle bogie at first, then design a scheme of single-axle driving bogie, using modern technology of urban mass traffic and high-speed motor train unit. After analyzing the applied forces state of balanced-beam in the tractive behavior or braking condition, we have primarily found out the designing rules of balanced-beam, and got its reasonable designing parameters.Via theories of rail vehicle dynamics, we build a mathematical model of single-axle bogie, and build a train unit model in the SIMPACK software, then execute dynamic calculating, get reasonable suspension parameters'. With the parameters, we have predicted the dynamic performance of train unit, and come to the conclusions following:1 The hunting stability of single-axle bogie is worse than conventional two-axle bogie, but can be improved by hunting-proof damper and lateral damper, and critical speed of single-axle bogie can reach 230km/h at most.2 The single-axle bogie's performance criteria of curve passing is excellent, its every criteria in steady-state is superior to conventional two-axle bogie, and it can be guided by creep forces on the curves which radius is bigger than 300m. The same as general two-axle bogie, the single-axle bogie's performance in hunting stability and curve passing is also in conflicting, when the parameters are in favor of hunting performance, the steady-state of curve passing need longer time, but all the final states of curve passing are the same.3 Because single-axle bogie passes all excitations of rail to car body, two-axle bogie transfer only half, the disturbances in car body using single-axle bogie is more, so the single-axle bogie's smoothness is not good.In total, the smoothness and lateral stability on the urban mass traffic rails of single-axle bogie have met the qualifications of interrelated standard, and it is very suitable for urban mass traffic lines which have many curves and most of which have small radius because of its predominant performance in curve passing. It is a new bogie at the glorious prospect.