摘要 |
PURPOSE:To facilitate the production of a cabinet for acoustic machinery having an excellent characteristics, by forming through heating and pressurizing a mixture consisting of ''Sirasu'' sand as an essential component and a small chip of wood as secondary component plus a binder componsed essentially of the thermoplastic resin. CONSTITUTION:A mixture 33 consists of a main aggregate composed essentially of a granule having <=2mm. average grain size, for instance, 0.5mm. such as ''Sirasu'' sand, granite, slate, metamorphic rock, gravel, pumice, etc., a secondary aggregate composed essntially of a small chip of wood having <=2mm. average grain size and a binder composed essentially of the polyethylene, polyvinyl chloride, nylon, etc. Such mixture is charged into a metallic mold 29 for speaker cabinet and then receives an application of pressure and heat. The mold 29 consists of an inner mold 30 and an outer mold 31. The mold 30 has a pore 32 for speaker. Thus five faces, i.g., a top plate 22, a bottom plate 23, side plates 24 and 25 plus a surface plate 26 of a cabinet are formed to one body. The mixing ratio expressed by weight of the material is preferably set at the (0.2-2) main aggregate, a slight amount of the secondary aggregate and 1 binder, respectively. In such way, a cabinet having an accurate measurement and excellent characteristics can be obtained in a simple method. |