抄録
In order to optimize the structure of the bellows installed in the engine exhaust system of a hydraulic excavator, the Taguchi method was applied to the design of the bellows structure. The relative displacement applied to the bellows in the actual mounting environment was set as input, and the stress generated on the bellows was set as output. In addition, the specifications of bellows structure were selected as control factors, the amount of displacement were selected as signal factor, and the displacement direction, the friction coefficient and the stress generation locations were selected as error factors. After assigning these factors to the L18 orthogonal table, calculations were performed according to the orthogonal table to derive the cause and effect diagram of the SN ratio and sensitivity. The result of deriving the proper structure of the bellows from the diagram was as follows; the material is SUS, the inner diameter is small, the height of the crowns is
high, the pitch of the crowns is large, the number of layers is small, the thickness of the plates is thin, the angle of the crown is large (Ω-type), and the number of crowns is large.
