Breathing apparatus and facepiece therefor
US6016802A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 17, 1997 |
| Grant date | Jan 25, 2000 |
| Priority date | — |
| Expiry date | Sep 17, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62B9/02
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A breathing apparatus comprises a supply of breathable gas and a facepiece by which breathable gas is supplied to a wearer, the facepiece including a supply valve for delivering gas to the interior of the facepiece, and an exhaust opening closeable by an exhaust valve for allowing the egress of exhaled gas from the facepiece. The exhaust valve comprises a movable valve member which, in a first position, closes the exhaust opening in the facepiece, in a second position is displaced toward the interior of the facepiece relative to the first position while still in sealing engagement with the exhaust opening to open the supply of breathable gas, and in a third position is displaced outwardly of the facepiece relative to the first position to open the exhaust opening to allow the egress of exhaled gas. The valve member is biased towards the second position by a single significant biasing means. A sealing element is preferably interposed between the valve member and the exhaust opening.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.