Optimization of Transmission Mount Bracket

The transmission mount in a powertrain mounting system is often a primary path for noise. This is especially the case when the transmission is mounted directly to the body without the benefit of a structural frame. The vehicle's structure at the mounting location is crucial in regard to noise transmission, durability and crash worthiness. The upper bracket attaches to the transmission by use of two horizontal fasteners. A limited vertical space is available for both the rubber mount and bracket. With limited rubber volume it is not possible to allow the rubber to be as soft as it is desired for maximum isolation of vibration. Therefore the bracket must be designed to be as stiff as possible.

Through the use of Computer Aided Engineering, an optimized bracket design for stiffness, strength and mass is obtained while still supporting a shortened development cycle. This paper focuses on the optimization of transmission cross member for modal requirements using MSC.NASTRAN and ANSYS Design space programs. The results are also compared with experimental data.