| 摘要 |
PROBLEM TO BE SOLVED: To provide an exterior case of a machinery, which eliminates leakage of a noise generated inside of the machinery.SOLUTION: In an exterior case 50 of a machinery, which has a surface structure constituted so as to form a housing space of the machinery inside the exterior case by a plurality of configuration surfaces, for example a cabin 51 or an engine cover 52 of a power shovel PC, a cell sound absorption body 30A consisting of a honeycomb cell which is a parallel aggregate of countless capillary tubular cells is formed on an inside surface of the configuration surface. Moreover, an exhaust port and the like are covered by a bottomed cell sound absorption body 30B. The bracing rigidity of the configuration surfaces of the exterior case 50 is strengthened by the cell sound absorption body 30A, and highly increased silencing by a synergic effect of a function of a honeycomb structure suppressing vibration of the exterior case 50 and a remarkable sound absorption function as the aggregate of countless cells is achieved. |
