Waterproof sound-transmissive cover, waterproof sound-transmissive cover member and acoustic device
US10798474B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 2017 |
| Grant date | Oct 6, 2020 |
| Priority date | — |
| Expiry date | Jul 7, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2499/11
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The waterproof sound-transmissive cover is characterized by providing a frequency response curve with a difference between a maximum sound pressure level and a minimum sound pressure level of 13.0 dB or less in the range of frequencies from 3 kHz to 8 kHz, and an insertion loss at 1 kHz of less than 14.0 dB, and said cover comprising: a porous film having (1) a water pressure resistance measured according to JIS L1092 water penetration test method B (high pressure method) of 20 kPa or more, and air permeability measured according to JIS L1096 method A (Frazier type method) of 3.0 cc/cm2·sec or more, and (2) a tensile strength measured according to ASTM standards D412 of 5.5N or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.