| 摘要 |
<p>The present invention pertains to hearing protective earplug constructions of the roll-down type. The earplug includes a resilient polymeric foam body (1) having a slow recovery viscoelastic nose section (3) and coextensive therewith, a relatively substantially faster recovery, more elastic tail section (5). In one aspect the constructions employ means to limit the depth of insertion of the earplug into the ear canal and to facilitate proper insertion thereof. In another aspect, the constructions employ polymeric foam bodies adapted to be compressed, inserted into the ear canal and there allowed to expand to obturate the ear canal and whose recovery time is markedly and inversely temperature dependent.</p> |
