Abstract: The motor bracket of the air conditioner outdoor unit is subject to a variety of excitation by the motor and fan, and is one of the important components in the structure of the whole machine. However, at present, there is less research on the vibration and noise failure form and mechanism generated by its excitation in the industry, and thus there is no clear and specific requirement on the design of vibration and noise of the motor bracket, which results in low design efficiency and potential market quality risk. We first analyze the modal simulation and working deformation test of the motor bracket to investigate the actual vibration form of the motor bracket; then we use the frequency sweeping test method to study the contribution of vibration noise of the motor bracket caused by various types of excitation, and its impact on the vibration noise of the whole machine. It is found that under the current structural form, only the fundamental frequency vibration excitation caused by fan dynamic balancing has a greater impact on the vibration noise of the whole machine, while other excitations have a smaller impact.

Key words: Bracket, Noise, Vibration