Abstract: The fit appearance gap between the air guide plate and the panel of the domestic air conditioner directly affects the user experience. The problems such as too large gap and uneven gap affect the product appearance grade. The fit appearance gap of the air guide plate is an important index to judge the product process level. Based on the abnormal gap in the production process of a split wall mounted internal machine, applies the tolerance simulation analysis tool to carry out the dimension chain simulation analysis, quotes the sensitivity and contribution analysis of the simulation software, and then identifies the key factors affecting the product quality. Combined with the mechanical principle and the investigation of the actual part processing level, it is found that the wave deformation of the inner air deflector is the direct cause of the abnormal gap. By adjusting the injection molding process parameters, improve and reduce the wave deformation degree of the inner air guide plate, and develop the profiling compression orthopedic process technology for shaping and curing, so as to significantly reduce the appearance matching gap of the whole machine and improve the consistency of product quality.

Key words: Tolerance simulation analysis, Clearance, Deformation, Key factors