| 摘要 |
PURPOSE:To obtain a catalyst capable of absorbing sound and treating exhaust gas by forming plural passages in the gas flow direction in the three-dimensional structure, closing the specified number of the passages on the gas inlet side and depositing a catalyst on the sheets forming the passages. CONSTITUTION:Two corrugated sheets 11 are matched with each other through a partition sheet 5 and inserted into an outer-wall sheet 10 to form twelve passages, for example, and a catalyst is deposited on the respective sheets. Shielding plates 4 are fixed to both end faces of the outer-wall sheet 10, 20-90% of the passages are closed by the shielding plates 4, and an air layer is formed in the closed passage. When the catalyst is set in an exhaust pipe, the exhaust gas introduced into the catalyst is rapidly contracted at the inlet and rapidly expanded at the outlet, and hence the noises are reduced. Besides, the noises introduced into the air layer are reduced by a resonance effect, etc. |
