摘要 |
1536089 Sound insulation BOSCHSIEMENS HAUSGERATE GmbH 10 Nov 1977 [17 Nov 1976] 46816/77 Heading F2X A self-supporting, sound insulating housing for a domestic appliance, e.g. a dish or laundry washing machine, is of sandwich construction and comprises wall members whose surface layers are of a high-grade plastics material and which have an intermediate layer containing a material having a density greater than that of the material of the surface layers. The surface layers may be of a thermoplastic such as polypropylene. The intermediate layer may comprise a thermoplastic such as polystyrol, preferably foamed, filled with a material having a density >2 g./c.c., e.g. red mud, pearl white or sand. Alternatively, the intermediate layer may comprise hard pitch having a m.p. > 75‹ C. Where both the surface layers and the intermediate layer are made of thermoplastics, the housing may be manufactured by means of a two-component injection moulding process. |