| 摘要 |
Articles such as motor cyclists safety helmets are manufactured by press or injection moulding non re- entrant parts (2,3;) and assembling the parts into completed articles by securement at lap or other inter-fitting joint formations formed on the parts. The parts can be of glass fibre reinforced synthetic resin and secured by adhesive but thermoplastic parts can be welded together. Helmet parts can comprise two parts joining on a vertical median plane; the parts may be differently coloured to provide a multi- coloured decorative effect. <IMAGE> |
