NOISE-PROOF COVER FOR INTERNAL-COMBUSTION ENGINE

摘要

PURPOSE:To reduce the weight and the cost by constructing the noise-proof cover for reducing the noise produced through driving of an internal-combustion engine with sound-absorbing member made by burning fiber mat of pressure mixed inorganic or organic fiber and molding into predetermined shape. CONSTITUTION:In an unit where an engine 10 is covered with a shroud 12 formed integrally together with the cylinder section 11, porous layer 13 having excellent sound-proof effect is employed at the inside while hard layer (tight layer) 14 having excellent sound-shield effect and rigidity is employed at the outside. When molding the sound-proof member constituting the shroud 12, inorganic or organic fibers such as long glass fiber, ceramic fiber, etc. are first cut down and mixed then roller press or needling is applied to produce a fiber mat. Then this mat is set into predetermined shape and burnt to produce a molded sound- proof member having porous layer at the inside and hard layer 14 at the outside.