Abstract: With the rapid increase of the large volume and multifunction refrigerator proportion, the improved design of the components unsteady noise has become a critical technological breakthrough. By analyzing the working principle and installation method of the electric valve, the unsteady noise in the electric valve was investigated. From the perspective of controlling the vibration and noise path, the improved methods were proposed, such as structure optimization, vibration isolation, material replacement and sound-absorbing design. In addition, the sound quality evaluation method was used to evaluate the user subjective feeling of the improved methods in noise improvement. Through evaluations, the optimal design which meets the user's demand was obtained, meanwhile the refrigerator sound quality level is improved.

Key words: Refrigerator unsteady noise, Electric valve, Installation structure, Improvement design, Sound quality evaluation