The Theoretical Research And Simulation Analysis On The Empty Set Of Gears Rattle Of The Transmission

In the automotive industry,the gear rattle noise of transmission may possibly occur,the noise can make the person feel fatigue and tired,it seriously affect the ride comfort of the vehicle and the product quality.It is an urgent problem in the auto transmission industry.There are few technical researches in this academic field,mainly using dynamic simulation software to analysis and solving specific problems by changing parameters to obtain the optimization design,which is time-consuming.Due to the theoretical research of this aspect is not perfect,there is no definite solution.In this paper the mathematical model of system dynamics analysis is used.By using the knowledge of dynamic system to analysis transmission gear rattle force,the laws between the related parameters and influencing factors and the function relations between rattle force and the influencing factors is obtained.The Adams simulation analysis is also verified.In this paper,the mathematical model of transmission gear rattle and vibration is first established and its natural frequency is calculated.We found the torsional vibration frequency of engine shaft is much lower than its natural frequency.Later,a certain type of auto transmission gear couple which considering the transmission input shaft torsional vibration and the bending and the bearing stiffness of transmission axle is taken as an example to study the main factors of gear rattle to obtain the relations between the related parameters and rattle force to reduce transmission rattle noise.The main research contents are as follows:(1)To study the process and the feature of the empty set of gear rattle.Establishing the mathematical and virtual prototype model of a single gear couple,studying the influence of mixed oil damping and the helix angle of the gear couple;(2)Establishing the empty set of gear rattle model which considering the torsional vibration of input axle to obtain the influence and the function relations between the engine and the gear couple parameters;(3)Establishing the empty set of gear rattle model which considering the torsional vibration of input axle as well as the bending and the bearing stiffness of transmission axle,to obtain the influence and the function relations between the engine and the gear couple parameters by theoretical analysis and simulation verification;(4)Considering the different number of cylinders and the type of engine(inline 4cylinder engine,pancake four-cylinder engine,the V6 and V8 engine cylinder engine)to theinfluence law of the empty set gear tapping force,and the research of primary and secondary relations between various influencing factors.By completing the model as well as theoretical analysis and simulation verification,this paper established the main factors influencing the transmission knocking noise and its function relations,giving auto transmission designers an effective method of reducing the noise of a transmission rattle noise.