Warning signal producing device for protective breathing apparatus
US4249473A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 1979 |
| Grant date | Feb 10, 1981 |
| Priority date | — |
| Expiry date | May 9, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8326
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A warning device for indicating a reduction of breathing gas supply pressure in an air breathing conduit includes a warning device member disposed in the breathing conduit which has a connection to the gas supply and is movable in response to a drop in the air supply pressure beyond the predetermined amount into at least a partially blocking position so as to increase the flow resistance through the breathing conduit so that the patient using the device is warned by the condition. The device includes a correction element connected to the conduit which moves the warning member in a direction away from the blocking position so that the warning cycle is again initiated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.