Respirator face mask
US4414973A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1981 |
| Grant date | Nov 15, 1983 |
| Priority date | — |
| Expiry date | Mar 10, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/789
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A respirator face mask formed from a silicone or other vulcanized rubber with a multi-compound curved face seal having a superior configuration for facial fit. The mask is held by four support buttons and two straps attached thereto having a reverse leverage pulldown effect to pull the mask into contact with the facial area. The four attachment means for the straps are eccentric buttons having an undercut that overrides a loop that can be easily disassociated when the attachment loop is reversed and pulled over the button. A concave configured sealing diaphragm on the exhalation valve provides for substantially uniform opening with less effort than is normally encountered in such valves. A staggered anti-inversion rib on the concave underside of the exhalation valve prevents the diaphragm from inverting to a convex configuration. The valve includes an exhalation valve stack and vent that can be covered at a sharply chamfered opening to provide for a pressure fit test. The inhalation port features two unique chamfered exterior rings which mate with a reverse chamfered cartridge. The inhalation valve is mounted on the threaded connector so as to form a slightly concave configuration …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.