| 摘要 |
The invention relates to using PA-ABS (polyacetal-alryl butadiene styrene) for injection moulding engineering and to a method for producing a lattice-type covering element for loudspeakers and ventilation openings, wherein the surface of said lattice-type element is substentially greater than the all-over surface of a spatial injection-mould body and the plastic volume is substentially less because of the lattice-type openings, an injection-moulding temperature is maintainable below 300 °C, in particular of 280 °C, flow paths can be exposed to injection up to 180 mm, in particular 220 mm, the injection moulding is carried out by means of a plurality of injection channels, neither ream on the visible face of the lattice-type covering element, neither joint line between two molten phases are visible, nor disturbing physical damage is happen. The inventive lattice-type covering elements are used for covering loudspeakers and ventilation cooling or heating orifices in land, water and aircrafts and for buildings and devices due to a high heat resistance of the PA-ABS plastic materials, thereby substituting actually used metal covering grid plates. When used for covering the ventilation orifices, said plates also serve as diffusers. |
