| 摘要 |
PURPOSE:To markedly reduce the noise in car interior by subjecting a ceiling steel plate to vibration suppressing and concentrated sound absorbing treatment. CONSTITUTION:A skin layer should be provided with an air flow resistance value of about 10-200c.g.s.rayls. The capationed lightweight ceiling member is produced by forming a molded ceiling basic member having a square concaved part having a side length of about 300-500mm., and a depth of about 10- 30mm. at the position corresponding to the overhead position of a driver's seat and an assistant's seat by a conventional molding method, and forming a skin layer having a specific air flow resistance value, on the car interior side of said molded ceiling member. |
