Respirator mask for positive pressure respirator equipment
US4905683A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 10, 1987 |
| Grant date | Mar 6, 1990 |
| Priority date | — |
| Expiry date | Jul 10, 2007 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62B18/02
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A respirator mask for positive pressure respirator equipment comprises several peripheral seal edges around the face of the mask wearer. It must be assured that in case of possible leaks of the seal edges no respiratory gas, in particular respiratory gas with increased oxygen concentration, escapes into the open. To check that there are no leaks of respiratory gas past the seal edges, one of the sealing cavities defined by the seal edges in the mask is connected to a connecting line. This cavity defines a control chamber. A flow indicating device is connected to the connecting line and is placed so that it is visible to the wearer. A valve is positioned in a part of the mask bounding the interior of the control chamber. The valve can be actuated to permit the flow of gas, for example exhaled gas, into the control chamber and out through the connecting line and flow indicating device. The wearer can determine what a normal flow value should be and, if the flow observed on the flow indicating device falls below this value, it is assumed that a leak has developed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.