Analysis and Optimization of the Hinge Mechanism of the Trunk Lid_Hinge Knowledge_Tallsen 1

The current hinge transmission system used in car trunks is designed for manual switching. Applying force to open and close the trunk requires considerable effort, which can be labor-intensive. To address this, there is a need to develop an electric trunk lid while maintaining the original trunk movement and position relationship. The four-link hinge system of the trunk needs to be optimized to increase the length of the force arm at the electric drive end and reduce the torque required for electric drive. However, the complexity of the trunk opening mechanism makes it difficult to obtain accurate and comprehensive data for system optimization through traditional design calculations.

Importance of Dynamic Simulation:

Dynamic simulation of the mechanism allows for more accurate determination of the motion state and force of the mechanism at any position. This is crucial in determining a reasonable mechanism design scheme. The trunk opening mechanism is a multi-link mechanism, and dynamic simulation has been successfully applied to analyze the dynamic characteristics of similar linkage mechanisms. Previous studies have also utilized simulation to optimize mechanism parameters, providing valuable insights for the dynamics research of automobile trunks.

Application of Dynamic Simulation in Automotive Design:

The method of dynamic simulation has been increasingly applied in the mechanism design of automobiles. Various studies have utilized this approach to analyze the ride comfort of articulated dump trucks on random roads, torque and power requirements for different opening speeds of electric scissor doors, door hinge design, front side seam line of the door, and the layout of torsion bar springs for trunk lids. These studies have demonstrated the feasibility of using dynamic simulation to assist in the design of automotive linkage mechanisms.

Adams Simulation Modeling:

In this study, an Adams simulation model was developed to analyze the trunk system. The model consisted of 13 geometric bodies, including the trunk lid, hinge bases, hinge rods, hinge struts, hinge connecting rods, pull rods, crank, and reducer components. The model was then imported into the automatic dynamic analysis system (Adams) for further analysis. Boundary conditions were defined to constrain the motion of the parts, and model properties such as friction coefficients and mass properties were defined. Additionally, the force applied by the gas spring was accurately modeled based on experimental stiffness parameters.

Simulation and Verification:

The simulation model was used to analyze the manual and electric opening of the trunk lid separately. The force values at the manual and electric force points were gradually increased, and the trunk lid opening angle was measured to determine the force required for full opening. The simulation results were then verified by measuring the opening forces using push-pull force gauges. The measured values were found to be consistent with the simulation results, confirming the accuracy of the analysis.

Mechanism Optimization:

Based on the torque measurements obtained during the simulation and verification process, it was determined that the torque required to open the trunk lid exceeded the design requirements at certain points. Therefore, the hinge system needed to be optimized to reduce the opening torque. Considering the limitations of installation space and structural layout, the positions of certain hinge components were adjusted to achieve a reduction in torque while maintaining the motion relationship and length of each rod. The optimized hinge system was analyzed using the simulation model, and it was found that the opening torque at the output shaft of the reducer and the joint between the tie rod and the base had been significantly reduced, meeting the design requirements.

In conclusion, this study successfully utilized Adams simulation modeling to analyze the dynamics of manual and electric opening methods for car trunk lids. The analysis results were verified through real-world measurements, confirming their accuracy. Furthermore, the hinge mechanism of the trunk lid was optimized based on the dynamic system model, resulting in a reduction in the electric opening force and better adherence to design requirements. The application of dynamic simulation in automotive mechanism design has proven to be effective and provides valuable insights for future design optimizations.