| 摘要 |
1,181,569. Laminates. LES ISOLANTS FRANCAIS. 24 Nov., 1967 [28 Nov., 1966], No. 53552/67. Heading B5N. A composite sound and vibration board comprises two superposed component boards, each having a plurality of longitudinally-extending recesses on its internal surface, the longitudinally-extending recesses in one of the component boards being opposite the longitudinally extending recesses in the other of the component boards, and a longitudinally-extending component disposed in each pair of opposed recesses, the depth of the longitudinally-extending component being substantially equal to the depth of the pair of opposed recesses. In preferred embodiments the recesses or troughs are of substantially trapezoidal cross-section with a component of substantially square cross-section and having a longitudinally extending aperture or of hexagonal cross-section. In addition the outer surface of each component board may have recesses or troughs, e.g. of triangular, rectangular or sinusoidal cross-section. The composite board is preferably formed of an elastomeric material. |
