Earplug
US4702238A · kind A · utility
Inventor
Key dates
| Filing date | Apr 3, 1986 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Apr 3, 2006 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F11/08
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An earplug for attenuating sound and providing a watertight seal at the auricle is provided which is made of solid, closed cell, slow recovery foam having an external flange adapted to extend beyond the auricle, the surface of the plug being convex to reflect away sound, and having an inwardly extending conical portion fitting into the auricle or cavum concha and the outer portion of the auditory canal sealing off the meatus of the external ear canal without substantially penetrating the external ear canal. The closed cell foam provides a multitude of convex and concave surfaces which dramatically reflect, dissipate and attenuate sound waves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.