Door Latch Integrity Study: Evaluation of Door Latch Failure Modes

摘要

This report contains the results of an investigation conducted by the VehicleResearch and Test Center (VRTC) to determine the potential for different door latch failure modes. In a previous study performed at the VRTC, several door latch failure mechanisms were identified which included structural failure, detent lever-fork bolt bypass, linkage activation, and inertial loading. All four of these failure mechanisms were evaluated in this study. Structural failure was evaluated by performing FMVSS 206 door latch tests, full door longitudinal and lateral tension tests similar to those for FMVSS 206, and simulated B-pillar twist latch tests using the GM Rotational Test fixture. Detent lever-fork bolt bypass was tested using a component level test fixture. Full door testing for detent lever-fork bolt bypass has been performed in a previous study. Linkage activation was evaluated in the full door longitudinal tension tests discussed previously. The doors were subjected to inertial loading in several different directions. The results of all the different types of testing conducted suggest that no one test procedure will determine the weak link in all types of latches. Several test procedures should be required to fully evaluate door latch strength.