Structure Optimization And Foundry Technology Design For A New Tapered Rotary Leaf Spring

The spring leaf was widely used in the truck. The friction was formed between the plates in the common spring leaf when the truck was moving, leading to frictional vibration and thus result in the noise induced and the stiffness increased.Based on the equivalent stress standard, a new tapered rotary leaf spring was designed. The calculative formula of rigidity was computed by using the unit load method and formula of torsion angle. By using the finite element software, the calculative formula was tested. Then, the size of the leaf spring was designed. Four kinds of design scheme were presented. To design a new leaf spring for the CA1091 light truck, the statics analysis and the dynamics analysis were tested. We contrasted our new spring leaf to the ordinary spring leaf. The weight was reduced by 40%, and the friction was avoided.The manufacturing technology of the leaf spring was determined. The filling process and the solidification process were analyzed by using ProCAST. By comparing scheme, the casting process was determined. Through orthogonal experiment, the factors which affected the quality of the casting were studied, such as the pouring temperature, the temperature of shell and the pouring time. When the pouring temperature was 1540 ℃, the temperature of shell was 700 ℃ and the pouring time was 8s, the liquid metal filling smoothly, the shrinkage of the casting was the least. Finally, using the ProCAST to predict the casting stress, the results showed that the maximum stress was 243MPa, appeared in the gate. As the performance of the casting was less affected, the casting with excellent comprehensive properties was determined.