Theoretical and experimental studies on the natural frequencies of fastener clips

The clamping force (elastic range) of the clip and the load-frequency-dependent stiffness of the elastic pad were not adequately accounted for the calculation of the natural frequency of the clip. In this paper, the clip's natural frequencies of a DT-III fastener system without and with a train load were first compared and analyzed to investigate the respective effect of the above two factors. Then, a finite element model consistent with the above hammer test conditions was established to calculate the natural frequencies of the clip without and with a train load, and the accuracy of the calculated results was verified by the above hammer test. The results showed clip clamping force and load-frequency-dependent stiffness of elastic pad are two key parameters to calculate the natural frequency of clip. The calculation errors of the natural frequency of the clip without and with a train load were 1.4 and 1.8 Hz by comprehensively considering the above two factors. The real natural frequency of the fastener clip changes dynamically between without and with a train load instead of a fixed value.

Automated summary

This study compares and analyzes the factors affecting the natural frequency of the clip, establishes a finite element model to calculate the natural frequency, and verifies the accuracy of the calculations. The results indicate that the clamping force of the clip and the load-frequency-dependent stiffness of the elastic pad are two key parameters.