A Disciplined Approach to Minimize Rattle Issues in Automotive Glove Box Assembly 2018-01-1481
Nowadays, perception of automotive quality plays a crucial role in customer decision of vehicle purchase. Hence, automotive OEM’s are now working on the philosophy of “Quality Sound”. Out of all the Noise, Vibration & Harshness (NVH) issues identified in a vehicle, the ranking of Buzz, Squeak & Rattle (BSR) stands high and glove box rattle is one of the issues that is continuously observed in all customer verbatim. Specific issues like lid rattle and latch rattle are predominant and gets worse over mileage accumulation. Also minimizing BSR issues in glove box is difficult due to complex latch mechanism. While deciding the bump stop specifications more weightage is given to efforts. The bump stop is selected in a way as not to increase the glove box opening and closing efforts, but the selected bump stops will not provide enough preload to glove box lid leading to rattle issues. Also, the contradictory requirements between efforts and rattle makes the scenario more difficult to fine tune bump stop specifications.
In the present study, an attempt is made to drive the glove box design from BSR point of view by carrying out rattle simulation on glove box assembly. The aim is to minimize the BSR issues in assembly without affecting glove box operating efforts. The methodology is implemented with realistic themes of finite element modelling and the analysis is performed by utilizing current software capabilities. Meaningful information has been extracted to analyze the influence of rubber bump stop design on glove box rattle issues. The bump stop pretension force (FP) and calculated dynamic force, (Fd) are key parameters in estimating the BSR performance of glove box assembly.
The present work is limited to minimize the rattle issues at glove box lid and latch interface alone. Internal latch rattles are out of scope of this study. The non-linear behavior of bump stop is not considered because of small deformation values.