| 摘要 |
<p>The invention relates to a process for obtaining a helmet for protection against mechanical shocks and to helmet carried out according to the process. According to the invention, the process consists in carrying out, from a textile material previously impregnated with phenol formaldehyde and polyvinylbutyral resins, known per se, a laminate comprising 18 discs, 13 of these discs being basic discs (1) and 5 intermediary discs (2), the basic discs (1) being divided into ten equal sectors (a), then the helmet calotte is preformed by arranging each disc into a preforming mould (3), pressing each disc with a resilient punch, in warm air stream, at a temperature of 70 ... 80 C, then the preformed helmet calotte is introduced into a compression mould heated at the temperature of 150 C and it is pressed for 20 minutes at a pressure of 40 bars.</p> |
